镁合金挤压变形的组织性能与工艺研究
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摘要
本文结合等通道角挤压技术(ECAE)和传统挤压技术成功设计出双变通道角挤压(DCCAP)和双向挤压(DDE)，并经过有限元模拟仿真和工厂实际挤压论证，能获得性能优越的AZ31镁合金挤压棒材，挤压温度范围为523~723K。对具有挤压织构的AZ31镁合金进行了组织和性能测试，实验结果表明晶粒细化和织构变化对AZ31镁合金的力学性能具有重要的影响。DCCAP和DDE挤压变形行为和晶粒细化机理做了一系列的探索分析。同时对挤压镁合金内部长条晶粒的形成以及其对性能的影响从力学和耐腐蚀性两方面展开了研究。此外，对具有典型织构的纯镁挤压材进行冷锻二次变形以及随后的退火静态再结晶，从内部组织(如孪晶，不同取向的原始晶粒等)对二次冷变形行为以及退火回复、静态再结晶形核和晶粒长大进行了分析。根据这些研究分析主要得到如下结论：
①对在723K下进行15h均匀化处理的AZ31镁合金试样进行不同挤压温度下的热挤压实验，发现DCCAP和DDE挤压技术能够有效的细化晶粒，其最小晶粒尺寸约为9和3μm，细化效果显著，且比ECAE和传统挤压更为有效。晶粒尺寸随挤压温度的升高而增大，随挤压比的升高而减小。523K挤压温度下，所得的基面{0001}织构与挤压方向(ED)呈一定角度，温度达到573K以及以上时，均获得基面{0001}与ED接近平行的织构。
②DCCAP挤压温度为523K和673K试样的屈服强度分别190MPa和178MPa，断裂强度分别为285MPa和276MPa，由于523K下并未发生充分动态再结晶导致其伸长率(11%)小于673K的(14%)，强度系数K和应变硬化指数分别为516MPa,0.17和544MPa,0.20；DDE挤压比为4.5时，挤压温度为523K，抗压强度达到414MPa，压缩率为16.27.％，伸长率为14.75%，屈服强度为200MPa；挤压比提高到10.1时，挤压温度为573K，抗压强度为435MPa，压缩率为19.5%，伸长率为18.6%，屈服强度为232MPa。挤压试样的抗压强度、压缩率和屈服强度值得到极大提高，在同等挤压比条件下，抗压强度、压缩率、伸长率和屈服强度值随挤压温度(≥573K)的升高呈减少趋势。
③DCCAP和DDE挤压后在模具转角和挤压比共同作用下能使等效应变值和等效应变速率最大值分别达到：1.44，3.1和1.93，4.1；且等效应力高达134MPa和142.96MPa。从动态再结晶理论上分析，DCCAP和DDE挤压技术具有较优的晶粒细化效果。DCCAP和DDE的变形区域均可分为压缩区，转角剪切区和挤压比变形区。其晶粒细化机制主要是发生连续动态再结晶(CDRX)，同时又由于对AZ31镁合金施加了剧烈的塑性应变，很有可能存在晶粒分解碎化。
④挤压比为10.1，挤压温度为573K的DDE挤压试样横截面晶粒组织热稳定现象可分为三个阶段，473~548K，晶粒平均尺寸随温度上升呈线性长大；548~673K，晶粒长大趋势趋于平缓；673K以后，晶粒迅速长大。在473~548，548~673，673~723K三个温度区间，其晶粒长大激活能分别为：80.1，18.1，97.8kJ/mol；且力学性能与Hall-Petch关系比较吻合。
⑤挤压长条晶粒主要是由不利于滑移变形的原始粗晶和孪晶间分割的原始晶粒受流变应力演变而成，且均围绕着<1120>轴向使得晶体的c轴垂直于挤压方向。在室温变形过程中，长条晶粒与周围细小晶粒的{0001}基面转动不协调性，致使长条晶界处积聚较大的应力易诱发压缩孪晶{1011}、{3032}、{1013}<3032>以及二次孪晶{1011}-{1012}，以致于促使裂纹产生，导致失效。长条晶粒的晶界处以及晶内局部地区存在位错塞积或者位错胞结构，最先形成腐蚀坑，DDE挤压技术比正挤压(FE)技术更为有效的改善内部组织尤其是长条晶，进而提高AZ31镁合金的耐腐蚀性能。
⑥挤压纯镁室温冷锻变形时，孪晶为重要的变形机制，起初主要以拉伸孪生{1012}<1011>为主；随着应变增加，c轴发生了严重的倾转，致使{1013}<3032>和{1011}<1012>大量产生。应变为6%时，大部分基面{0001}与挤压方向呈45°；应变为12%,16%和20%时，大部分基面与锻造方向(FD)相垂直。14%冷锻变形的纯镁在退火时能发生静态再结晶(SRX)细化晶粒由原始挤压态的80μm至25μm。SRX的主要形核点为三叉晶，压缩孪晶和二次孪晶等。拉伸孪晶处的SRX形核几乎与基体保持相同的位向关系，三叉晶界处形成的SRX和基体取向不同，但是却不能改变整个织构取向分布。SRX和原始晶粒的c轴倾向于FD方向生长。由退火硬度曲线能明确界定出回复、再结晶和晶粒长大三个阶段，提高退火温度可促进SRX和晶粒长大，同时也减少了回复和SRX的持续时间。
This paper successfully designed double change channel angular pressing (DCCAP)and dural directional extrusion (DDE) combined the technology of equal channelangular extrusion (ECAE) and traditional extrusion, and through the argument of thefinite element simulation and actual extrusion factory, superior performance of extrudedAZ31magnesium alloy bar can be obtained, the extrusion temperature range from513Kto723K. We successfully carried out microstructure and properties for extruded AZ31with typical extrusion texture, the results show that grain refinement and texturevariation have an important effect on the mechanical properties of AZ31alloy. Thedeformation behaviors and the mechanism of grain refinement for DCCAP and DDEtechnology were analyzed via a series of research theory. Meanwhile, the elongatedgrains formation, and its influence on mechanical and corrosion properties were furtherstudied. In addition, the secondly cold forging deformation to extruded pure magnesiumpipe and subsequent static recrystallization (SRX) through annealing process were alsoanalyzed mainly from internal microstructure (such as twin, grain orientation et al) onthe cold deformation behavior and annealing restore, SRX nucleation and grain growth.According to the above research, we can draw some conclusions as follow:
①The as-cast AZ31magnesium alloy specimens homogenized at723K for15hwere extruded at different extrusion temperature. The results show that DCCAP andDDE are very effective to refine grains, and their minmum sizes are about9and3μm,respectively. The refinement effect is better than ECAE and traditional extrusion. Thegrain size increases with the extrusion temperature elevated, while decreases with theincrease of extrusion ratio. Basal plane {0001} texture present some angular withextrusion direction (ED), but when the temperature up to573K, basal planes {0001}texture are nearly parallel with ED.
②For DCCAP-ed AZ31alloys extruded at523K and673K, the yield strength are190MPa and178MPa, and the fracture strength are285MPa and276MPa, and thefracture strain are11%and14%, and strength factor K and strain hardening exponent nare516MPa,0.17and544MPa,0.20, respectively. This can be attributed to the co-effectof grain size and the extent of DRX; As for DDE-ed AZ31alloys with extrusion ratio4.5and extrusion temperature523K, compressive strength, compressive ratio,elongation and yield strength are up to414MPa,16.27%,14.75and200MPa, respectively. As the extrusion ratio up to10.1, the extrusion temperature at573K,compressive strength, compressive ratio, elongation and yield strength are increased to435MPa,19.5%,18.6%and232MPa. All of extruded AZ31alloys with the sameextrusion ratio, compressive strength, compressive ratio, elongation and yield strengthare presented a decrease tendency with the increase of temperature (≥573K).
③The effective strain and strain ratio of DCCAP and DDE can get up to1.44,3.1, and1.93,4.1, meanwhile, effective stress are134MPa and142.96MPa, respectively.Thus, DCCAP and DDE will have excellent grain refinement effect via the theory ofdynamic recrystallization (DRX). The deformation region of DCCAP and DDE can bedivided into upsetting region, shearing region and extrusion ratio region. Themechanism of grain refinement is continuous dynamic recrystallization (CDRX).Simultaneously, coarse grains are likely to subdivide into fine grains due to higherplastic strain imposed.
④For DDE-ed AZ31alloys extruded at573K and extrusion ratio of10.1, themicrostructure thermostbilization of transverse plane can be divided into three stages:473~548K, grains are gentle grow linearly;548~673K, grain growth is not changeobviously and placid trend; higher than673K, grains grow promptly. The activationenergies of grains growth for the three stages are80.1,18.1and97.8KJ/mol,respectively. Morever, the mechanical properties are in a good agreement withHall-Petch relationship.
⑤Elongated grains formation can be attributed to flow stress on original coarsegrains disadvantage of basal slip and some original grains divided by twinning. The caxis of elongated grains are vertical to ED aroud <1120> direction. During thedeformation process at room temperature, the roatation extent of elongated grains andfine grains is different, resulting in accumulative stress at grain boundaries, thus triggercontraction twinning {1011}、{3032}、{1013}<3032> and double twinning{1011}-{1012}, finally, lead to fracture. There are many tangled dislocations and cellstructure at grain boundaries or in grains some local region, where are vulnerable tocorrosion pits. DDE can better improve the inner microstructure especially elongatedgrains, then, improve AZ31alloys the property to resist corrosion.
⑥Twinning is an important deformation mechanism for cold forging on extrudedpure Magnesium, at the outset, extension twinning {1012}<1011> is the main kind oftwinning; With the increase of strain, c axis take place rotation, result in forming largeamount of contraction twinning {1013}<3032> and{1011}<1012>. Most of {0001}basal planes are keep a angle of45°with forging direction (FD) for6%samples,while, most of basal planes {0001} are pendicular to FD for the samples under strains of12%,16%and20%. The grains of14%cold forging samples can be refined from80μmto25μm via annealing SRX. The SRX nucleation sites are mainly at triple boundaryjunctions, contraction twinning and double twinning et al. SRX grains formed byextension twinning are keep almost the same orientation with its matrix, SRX grainsderived from triple boundary junctions are at different orientation from the matrix, butthis can not change the whole texture distribution. The growth of SRX and originalgrains inclined to FD. It can obviously define the stages of restore, SRX and graingrowth via the Hv curves. Increasing annealing temperature can contribute to SRXnucleation and growth, and lessen the duration of dynamic restore and SRX.
①对在723K下进行15h均匀化处理的AZ31镁合金试样进行不同挤压温度下的热挤压实验，发现DCCAP和DDE挤压技术能够有效的细化晶粒，其最小晶粒尺寸约为9和3μm，细化效果显著，且比ECAE和传统挤压更为有效。晶粒尺寸随挤压温度的升高而增大，随挤压比的升高而减小。523K挤压温度下，所得的基面{0001}织构与挤压方向(ED)呈一定角度，温度达到573K以及以上时，均获得基面{0001}与ED接近平行的织构。
②DCCAP挤压温度为523K和673K试样的屈服强度分别190MPa和178MPa，断裂强度分别为285MPa和276MPa，由于523K下并未发生充分动态再结晶导致其伸长率(11%)小于673K的(14%)，强度系数K和应变硬化指数分别为516MPa,0.17和544MPa,0.20；DDE挤压比为4.5时，挤压温度为523K，抗压强度达到414MPa，压缩率为16.27.％，伸长率为14.75%，屈服强度为200MPa；挤压比提高到10.1时，挤压温度为573K，抗压强度为435MPa，压缩率为19.5%，伸长率为18.6%，屈服强度为232MPa。挤压试样的抗压强度、压缩率和屈服强度值得到极大提高，在同等挤压比条件下，抗压强度、压缩率、伸长率和屈服强度值随挤压温度(≥573K)的升高呈减少趋势。
③DCCAP和DDE挤压后在模具转角和挤压比共同作用下能使等效应变值和等效应变速率最大值分别达到：1.44，3.1和1.93，4.1；且等效应力高达134MPa和142.96MPa。从动态再结晶理论上分析，DCCAP和DDE挤压技术具有较优的晶粒细化效果。DCCAP和DDE的变形区域均可分为压缩区，转角剪切区和挤压比变形区。其晶粒细化机制主要是发生连续动态再结晶(CDRX)，同时又由于对AZ31镁合金施加了剧烈的塑性应变，很有可能存在晶粒分解碎化。
④挤压比为10.1，挤压温度为573K的DDE挤压试样横截面晶粒组织热稳定现象可分为三个阶段，473~548K，晶粒平均尺寸随温度上升呈线性长大；548~673K，晶粒长大趋势趋于平缓；673K以后，晶粒迅速长大。在473~548，548~673，673~723K三个温度区间，其晶粒长大激活能分别为：80.1，18.1，97.8kJ/mol；且力学性能与Hall-Petch关系比较吻合。
⑤挤压长条晶粒主要是由不利于滑移变形的原始粗晶和孪晶间分割的原始晶粒受流变应力演变而成，且均围绕着<1120>轴向使得晶体的c轴垂直于挤压方向。在室温变形过程中，长条晶粒与周围细小晶粒的{0001}基面转动不协调性，致使长条晶界处积聚较大的应力易诱发压缩孪晶{1011}、{3032}、{1013}<3032>以及二次孪晶{1011}-{1012}，以致于促使裂纹产生，导致失效。长条晶粒的晶界处以及晶内局部地区存在位错塞积或者位错胞结构，最先形成腐蚀坑，DDE挤压技术比正挤压(FE)技术更为有效的改善内部组织尤其是长条晶，进而提高AZ31镁合金的耐腐蚀性能。
⑥挤压纯镁室温冷锻变形时，孪晶为重要的变形机制，起初主要以拉伸孪生{1012}<1011>为主；随着应变增加，c轴发生了严重的倾转，致使{1013}<3032>和{1011}<1012>大量产生。应变为6%时，大部分基面{0001}与挤压方向呈45°；应变为12%,16%和20%时，大部分基面与锻造方向(FD)相垂直。14%冷锻变形的纯镁在退火时能发生静态再结晶(SRX)细化晶粒由原始挤压态的80μm至25μm。SRX的主要形核点为三叉晶，压缩孪晶和二次孪晶等。拉伸孪晶处的SRX形核几乎与基体保持相同的位向关系，三叉晶界处形成的SRX和基体取向不同，但是却不能改变整个织构取向分布。SRX和原始晶粒的c轴倾向于FD方向生长。由退火硬度曲线能明确界定出回复、再结晶和晶粒长大三个阶段，提高退火温度可促进SRX和晶粒长大，同时也减少了回复和SRX的持续时间。
This paper successfully designed double change channel angular pressing (DCCAP)and dural directional extrusion (DDE) combined the technology of equal channelangular extrusion (ECAE) and traditional extrusion, and through the argument of thefinite element simulation and actual extrusion factory, superior performance of extrudedAZ31magnesium alloy bar can be obtained, the extrusion temperature range from513Kto723K. We successfully carried out microstructure and properties for extruded AZ31with typical extrusion texture, the results show that grain refinement and texturevariation have an important effect on the mechanical properties of AZ31alloy. Thedeformation behaviors and the mechanism of grain refinement for DCCAP and DDEtechnology were analyzed via a series of research theory. Meanwhile, the elongatedgrains formation, and its influence on mechanical and corrosion properties were furtherstudied. In addition, the secondly cold forging deformation to extruded pure magnesiumpipe and subsequent static recrystallization (SRX) through annealing process were alsoanalyzed mainly from internal microstructure (such as twin, grain orientation et al) onthe cold deformation behavior and annealing restore, SRX nucleation and grain growth.According to the above research, we can draw some conclusions as follow:
①The as-cast AZ31magnesium alloy specimens homogenized at723K for15hwere extruded at different extrusion temperature. The results show that DCCAP andDDE are very effective to refine grains, and their minmum sizes are about9and3μm,respectively. The refinement effect is better than ECAE and traditional extrusion. Thegrain size increases with the extrusion temperature elevated, while decreases with theincrease of extrusion ratio. Basal plane {0001} texture present some angular withextrusion direction (ED), but when the temperature up to573K, basal planes {0001}texture are nearly parallel with ED.
②For DCCAP-ed AZ31alloys extruded at523K and673K, the yield strength are190MPa and178MPa, and the fracture strength are285MPa and276MPa, and thefracture strain are11%and14%, and strength factor K and strain hardening exponent nare516MPa,0.17and544MPa,0.20, respectively. This can be attributed to the co-effectof grain size and the extent of DRX; As for DDE-ed AZ31alloys with extrusion ratio4.5and extrusion temperature523K, compressive strength, compressive ratio,elongation and yield strength are up to414MPa,16.27%,14.75and200MPa, respectively. As the extrusion ratio up to10.1, the extrusion temperature at573K,compressive strength, compressive ratio, elongation and yield strength are increased to435MPa,19.5%,18.6%and232MPa. All of extruded AZ31alloys with the sameextrusion ratio, compressive strength, compressive ratio, elongation and yield strengthare presented a decrease tendency with the increase of temperature (≥573K).
③The effective strain and strain ratio of DCCAP and DDE can get up to1.44,3.1, and1.93,4.1, meanwhile, effective stress are134MPa and142.96MPa, respectively.Thus, DCCAP and DDE will have excellent grain refinement effect via the theory ofdynamic recrystallization (DRX). The deformation region of DCCAP and DDE can bedivided into upsetting region, shearing region and extrusion ratio region. Themechanism of grain refinement is continuous dynamic recrystallization (CDRX).Simultaneously, coarse grains are likely to subdivide into fine grains due to higherplastic strain imposed.
④For DDE-ed AZ31alloys extruded at573K and extrusion ratio of10.1, themicrostructure thermostbilization of transverse plane can be divided into three stages:473~548K, grains are gentle grow linearly;548~673K, grain growth is not changeobviously and placid trend; higher than673K, grains grow promptly. The activationenergies of grains growth for the three stages are80.1,18.1and97.8KJ/mol,respectively. Morever, the mechanical properties are in a good agreement withHall-Petch relationship.
⑤Elongated grains formation can be attributed to flow stress on original coarsegrains disadvantage of basal slip and some original grains divided by twinning. The caxis of elongated grains are vertical to ED aroud <1120> direction. During thedeformation process at room temperature, the roatation extent of elongated grains andfine grains is different, resulting in accumulative stress at grain boundaries, thus triggercontraction twinning {1011}、{3032}、{1013}<3032> and double twinning{1011}-{1012}, finally, lead to fracture. There are many tangled dislocations and cellstructure at grain boundaries or in grains some local region, where are vulnerable tocorrosion pits. DDE can better improve the inner microstructure especially elongatedgrains, then, improve AZ31alloys the property to resist corrosion.
⑥Twinning is an important deformation mechanism for cold forging on extrudedpure Magnesium, at the outset, extension twinning {1012}<1011> is the main kind oftwinning; With the increase of strain, c axis take place rotation, result in forming largeamount of contraction twinning {1013}<3032> and{1011}<1012>. Most of {0001}basal planes are keep a angle of45°with forging direction (FD) for6%samples,while, most of basal planes {0001} are pendicular to FD for the samples under strains of12%,16%and20%. The grains of14%cold forging samples can be refined from80μmto25μm via annealing SRX. The SRX nucleation sites are mainly at triple boundaryjunctions, contraction twinning and double twinning et al. SRX grains formed byextension twinning are keep almost the same orientation with its matrix, SRX grainsderived from triple boundary junctions are at different orientation from the matrix, butthis can not change the whole texture distribution. The growth of SRX and originalgrains inclined to FD. It can obviously define the stages of restore, SRX and graingrowth via the Hv curves. Increasing annealing temperature can contribute to SRXnucleation and growth, and lessen the duration of dynamic restore and SRX.
引文
[1] H. Li, E. Hsu, J. Szpunar, R. Verma, J.T. Carter. Determination of Active Slip/TwinningModes in AZ31Mg Alloy Near Room Temperature [J]. Journal of Materials EngineeringPerformance,2007,16:321-326.
[2] I. J. Polmear. Magnesium alloys and applications [J]. Materials Science and Technology,1994,10(2):1-16.
[3]陈振华,严红革,陈吉华.镁合金[M].北京:化学工业出版社,2004.
[4]刘正,张奎,曾小勤.镁基轻质合金理论基础及其应用[M].北京：机械工业出版社，2002.
[5]余琨,黎文献,王日初,等.变形镁合金的研究、开发和应用[J].中国有色金属学报,2003,13(2):277~288.
[6]崔昆.钢铁材料及有色金属材料[M].北京:机械工业出版社,1986.
[7] Elektron, Magnesium Alloys Handbook [M], Magnesium Elektron Ltd,1953.
[8]张津,章宗和,曾苏民等.镁合金及应用[M].北京:化学工业出版社，2004.
[9] Agnew S R O Z. Continuous, large strain, tension/compression testing of sheet material [J].International Journal of Plasticity,2005,(21):1161-1193.
[10] Taylor, G I. Plastic strain in metals [J]. Journal of the Institute of Metals,1938,(62):307-324.
[11] J. Jiang, A. Godfrey, W. Liu, et al. Microtexture evolution via deformation twinning and slipduring compression of magnesium alloy AZ31[J]. Materials Science and Engineering A,2008,(483–484):576–579.
[12] D. J. Bacon, V. Vitek. Atomic-scale modeling of dislocations and related properties in thehexagonal-close-packed metals [J]. Metallurgical and Materials Transactions,2002,33A:721-733.
[13] M.Mabuchi. Materials Transaction. Japan Institute of Metals,1995,36:1249-1254.
[14] M.R.Barnett, M.D.Nave, C.J.Bettles. Deformation microstructures and textures of some coldrolled Mg alloys [J]. Materials science and Engineering A,2004,(386):205-211.
[15] Perez-Prado.M.T, Del Valle.J.A. Microstructural Evolution During Large Strain Hot Rollingof an AM60Mg Alloy [J]. Scripta Materialia,2004,50(5):661-667.
[16] Chang.T.C, Wang.J.Y. Grain Refining of Magnesium Alloy AZ31by Rolling [J]. Journal ofMaterials Processing Technology,2003,140(3):588-593.
[17] Perez-prado.M.T, Del Valle.J.A, Ruano.O.A. Effect of Sheet Thickness on the MicrostructuralEvolution of an AZ61Mg Alloy during Large Strain Hot Rolling [J]. Scripta Materialia,2004,50(5):667-673.
[18]王新云，闫洪，胡国安等. AZ31变形镁合金挤压成形工艺研究[0]. http://www.paper.edu.cn.
[19] Murai.T, Matsuoka.S, Miyamoto.S. Effects of extrusion conditions on microstructure andmechanical properties of AZ31B magnesium alloy extrusions [J]. Journal of MaterialsProcessing Technology,2003,141(2):207-215.
[20] Lapovok.R.Y, Barnett.M.R, Davies.C.H.J. Construction of extrusion limit diagram for AZ31magnesium alloy by FE simulation [J]. Journal of Materials Processing Technology,2004,146(3):408-413.
[21] Kleiner.S, Uggowitzer.P.J. Mechanical anisotropy of extruded Mg-6%Al-1%Zn alloy [J].Materials Science and Engineering A.,2004,(379):258-267.
[22] Ogawa.N, Shiomi.M, Osakakd. Forming limit of magnesium alloy at elevated temperaturesfor precision forging [J]. International Journal of Machine tools&manufacture,2002,(42):607-614.
[23]张士宏,王忠堂.镁合金的塑性加工工艺[J].金属成形工艺,2002,20(5):1-3.
[24] Aghion E, Eliezer D. Magnesium and magnesium alloys-Science, Technology andApplication [M]. Israel: Avi moshe Bregman Ltd,2004.
[25] Shan DB, Xu WC, Lu Y. Study on precision forging technology for a complex-shaped lightalloy forging [J]. Journal of Materials Processing Technology,2004,(151):289-293.
[26] Kawasaki M, Langdon TG. Principles of superplasticity in ultrafine-grained materials [J].Journal of Materials Science,2007,42:1782-1796.
[27] Figueiredo RB, Langdon TG. Strategies for achieving high strain rate superplasticity inmagnesium alloys processed by equal-channel angular pressing [J]. Scripta Materialia.2009,61(1):84-87.
[28] Watanabe.H, Mukai.T, Ishikawa.K. High-strain-rate superplasticity at low temperature in aZK61magnesium alloy produced by power metallurgy [J]. Scripta Materialia,1999,41(2):209-213.
[29] Watanabe.H, Mukai.T, Ishikawa.K, Higashi.K. High-strain-rate superplasticity in an AZ91magnesium alloy processed by ingot metallurgy route [J]. Materials Transactions,2002,43(1):78-93.
[30] Watanabe.H, Mukai.T, Ishikawa.K. Superplasticity of a particle-strengthened WE43magnesium alloy [J]. Materials Transactions,2001,42(1):157-163.
[31]洪慎章.冷挤压技术[M].北京：机械工业出版社，2005.
[32] Ravi Kumar NV, Blandin JJ, Desra YCet al. Grain refinement in AZ91magnesium alloyduring thermomechanical processing [J]. Materials Science and Engineering A,2003,359(1-2):150-157.
[33] Figueiredo RB, Langdon TG. Grain refinement and mechanical behavior of a magnesiumalloy processed by ECAP [J]. Journal of Materials Science,2010,45:4827-4836.
[34] Shahzad M, Wagner L. Influence of extrusion parameters on microstructure and texturedevelopments, and their effects on mechanical properties of the magnesium alloy AZ80[J].Materials Science and Engineering A,2009,506(1-2):141-147.
[35] El-Morsy A., Ismail A, Waly M. Microstructural and mechanical properties evolution ofmagnesium AZ61alloy processed through a combination of extrusion and thermomechanicalprocesses [J]. Materials Science and Engineering A,2008,486(1-2):528-533.
[36] Beer AG， Bamett MR. The influence of twinning on the hot working flow stress andmicrostructural evolution of magnesium alloy AZ31[J]. Materials Science Forum,2005,488-489:611-614.
[37]张广俊，龙思远，曹凤红. AZ81镁合金挤压组织和性能研究[J].材料导报，2008,22:381-383.
[38]石磊，李继文，李永兵等. AZ31镁合金热挤压变形和力学性能分析[J].锻压技术，2009,34(6):35-38.
[39]陈国清，宋军辉，付雪松等.连铸AZ31镁合金的热挤压变形组织和性能[J].塑性工程学报，2009,16(6):50-55.
[40]胡燕辉，李建国，谭敦强.坯料细化处理对AZ31镁合金挤压组织的影响[J].轻合金加工技术，2010,38(3):42-46.
[41]尹从娟，张星，张治民.热挤压工艺对AZ31镁合金组织性能的影响[J].热加工工艺，2007,36(21):63-67.
[42]曲家惠，岳明凯，黄涛. AZ31镁合金在不同挤压比和挤压温度下的织构演变[J].沈阳理工大学学报，2009,28(2):48-51.
[43] Segal V M, Reznikov V I. Plastic working of metals by simple shear [J]. Russian Metallugy,1981,1:99-105.
[44] Kaibyshev R, Mazurina I. Mechanisms of grain refinement in aluminum alloys during severeplastic deformation [J]. Materials Science Forum,2004,467-470:1251-1260.
[45] Segal V M. Equal channel angular extrusion: from macromechanics to structure formation [J].Materials Science and Engineering A,1999,271(1-2):322-333.
[46] Mabuchi M, Iwasaki H, Yanase K, Higashi K. Low temperature superplasticity in an AZ91magnesium alloy processed by ECAE [J]. Scripta Materialia,1997,36(6):681-686.
[47] Wu D, Chen RS, Han EH. Bonding interface zone of Mg-Gd-Y/Mg-Zn-Gd laminatedcomposite fabricated by equal channel angular extrusion [J]. Transactions of NonferrousMetals Society of China,2010,20: S613-S618.
[48] Liu XB, Chen RS, Han EH. Preliminary investigations on the Mg-Al-Zn/Al laminatedcomposite fabricated by equal channel angular extrusion [J]. Journal of Materials ProcessingTechnology,2009,209(10):4675-4681.
[49] Song D, Ma AB, Jiang JH, Lin PH, Yang DH, Fan JF. Corrosion behaviour of bulk ultra-finegrained AZ91D magnesium alloy fabricated by equal-channel angular pressing [J]. CorrosionScience,2011,53(1):362-373.
[50] Birbilis N, Ralston KD, Virtanen S, Fraser HL, Davies CHJ. Grain character influences oncorrosion of ECAPed pure magnesium [J]. Corrosion Engineering Science and Technology,2010,45(3):224-230.
[51] Zhao ZD, ChenQA, Chao HY, Hu CK, Huang SH. Influence of equal channel angularextrusion processing parameters on the microstructure and mechanical properties ofMg-Al-Y-Zn alloy [J]. Materials and Design,2011,32(2):575-583.
[52] Segal V M. Slip line solutions, deformation mode and loading history during equal channelangular extrusion [J]. Materials Science and Engineering A,2003,345(1-2):36-46.
[53]杜忠泽,冯广海,符寒光,王经涛,赵西成. ECAP变形与材料组织性能控制的研究[J].材料工程,2006(3):64-68.
[54] Wang QD, Chen YJ, Lin JB, Zhang LJ, Zhai CQ. Microstructure and properties of magnesiumalloy processed by a new severe plastic deformation method [J]. Materials Letters,2007,61(23-24):4599-4602.
[55] Jahedi M, Paydar MH. Three-dimensional finite element analysis of torsion extrusion (TE) asan SPD process [J]. Materials Science and Engineering A,2011,528(29-30):8742-8749.
[56] Azushima A, Aoki K. Properties of Ultrafine-grained Steel by Repeated Shear Deformation ofSide Extrusion Process [J]. Materials Science and Engineering A,2002,377(1–2):45–49.
[57] Azushima A, Aoki K, Inoue T. Properties of Ultra Low Carbon Steel Produced by RepetitiveShear Deformation of Side Extrusion [J]. Tetsu to Hagane,2001,87(12):762–766.
[58] Aoki K, Kimura Y, Asada Y, Azushima A. Creation ofHigh Strength Carbon Steels byRepetitive Shear Deformation Process and Heat Treatment [J]. Proceedings of the7thInternational Conference on Technology of Plasticity,2002,1195-1200.
[59] Nakashima K, Horita Z, Nemoto M, Langdon TG. Development of a Multi-pass Facility forEqual-channel Angular Pressing to High Total Strains [J]. Materials Science and EngineeringA,2000,281(1-2):82-87.
[60] Liu ZY, Liang GX, Wang ED, Wang ZR. The Effect of Cumulative Large Plastic Strain on theStructure and Properties of a Cu–Zn Alloy [J]. Materials Science and Engineering A,1998,242(1-2):137-140.
[61] Ono M, Mizufune H, Narita M. Development of Semi-Continuous4Stage ECAE Method [J].Proceedings of the7th International Conference on Technology of Plasticity, Yokohama,2002,1249-1254.
[62] Rosochowski A, Olejnik L. Numerical and Physical Modeling of Plastic Deformation in2-turn Equal Channel Angular Extrusion [J]. Journal of Materials Processing Technology,2002,125-126:309-316.
[63] Rosochowski A, Rodiet R, Lipinski P. Finite Element Simulation of CyclicExtrusion-compression [J]. Proceedings of the8th International Conference on MetalForming Krakow,2000,3-7,2530-3259.
[64] Richert M, McQueen HJ, Richert J. Microband Formation in Cyclic Extrusion Compressionof Aluminum [J]. Canadian Metallurgical Quarterly,1998,37(5):449-457.
[65] Richert M, Liu Q, Hansen N. Microstructural Evolution Over A Large Strain Range inAluminium Deformed by Cyclic-Extrusion–Compression[J]. Materials Science andEngineering A,1999,268(1-2):275-283.
[66] Aizawa T, Katsuzawa K, Kihara J. Mechano-Metallurgical Processing for Direct Fabricationof Solid Non-equilibrium Phase [J]. Faculty of Engineering University of Tokyo Series B,1993,42(3):261-279.
[67] Neugebauer R, Glass R, Hoffmann M, Putz M. Spin Extrusion—A New Partial FormingTechnology based on7NC-Axes Machining [J]. CIRP Annals,2005,54(1):241-244.
[68] Ha11EO.The deformation and ageing of mild steel: III discussion of results [J]. Proceedingsof the Physical Society of London,1951,(64):747-753.
[69] Petch NJ. The cleavage strength of polycrystals [J]. Journal of the Iron and Steel Institute,1953,(174):25-28.
[70] Kim WJ, Hong SI, Kim YS. Texture development and its effect on mechanical properties ofan AZ61Mg alloy fabricated by equal channel angular pressing [J]. Acta Materialia,2003,(51):3293-3307.
[71]佐藤雅彦,薄板压延.秘制造工程诸特性[J].轻金属,2004,11:465.
[72] Kim HK, Kim WJ. Microstructural instability and strength of an AZ31Mg alloy after severeplastic deformation [J]. Materials Science and Engineering A,2004,385(1-2):300-308.
[73] Lu LW, Liu TM, Chen Y, Wang LG, Wang ZC. Double Change Channel Angular Pressing ofMagnesium Alloys AZ31[J]. Materials and Design,2012,35:138-143
[74] Lu LW, Liu TM, Jiang S, Pan FS, Liu Q, Wang ZC. Microstructure and mechanical propertyof dual-directional-extruded Mg alloy AZ31[J]. Materials Science and Engineering A,2010,527:4050–4055.
[75] Rao KP, Prasad YVRK, Suresh K. Materials modeling and simulation of isothermal forging ofrolled AZ31B magnesium alloy: Anisotropy of flow [J]. Materials and Design,2011,32:2545-2553.
[76] Das S, Lim NS, Seol JB, Kim HW, Park CG. Effect of the rolling speed on microstructuraland mechanical properties of aluminum-magnesium alloys prepared by twin roll casting [J].Materials and Design,2010,31:1633-1638.
[77] Gong XB, Li H, Suk BK, Cho JH, Li S. Microstructure and mechanical properties of twin-rollcast Mg–4.5Al–1.0Zn sheets processed by differential speed rolling [J]. Materials and Design,2010,31:1581-1587.
[78] Masoudpanah SM, Mahmudi R. The microstructure, tensile, and shear deformation behaviorof an AZ31magnesium alloy after extrusion and equal channel angular pressing [J]. Mater-ials and Design,2010,31:3512-3517.
[79] Ion SE, Humphreys FJ, White SH. Dynamic recrystallisation and the development of microstructure during the high temperature deformation of magnesium [J]. Acta Metallurgica,1982,30:1909-1919.
[80]刘楚明，刘子娟，朱秀荣，周海涛.镁及镁合金动态再结晶研究进展[J].中国有色金属学报，2006,16(1):1-12.
[81] Igarashi M, Khantha M, Vitek V. N-body inter-atomic potentials for hexagonal close-packedmetals [J]. Philosophical Magazine B,1991,63(3):603-627.
[82] Gourdet S, Montheillet F. A model of continuous dynamic recrystallization [J]. ActaMaterialia,2003,51:26852699.
[83]周海涛. AZ61镁合金高温塑性变形行为及管材热挤压研究[D].上海：上海交通大学,2004.
[84] Galiyev A, Kaibyshev R, Gottstein G. Correlation of plastic deformation and dynamicrecrystallization in magnesium alloy ZK60[J]. Acta Materialia,2001,49:1199-1207.
[85] Belyakov A, Miura H, Sakai T. Dynamic recrystallization under warm deformation of a304type austenitic stainless steel [J]. Materials Science and Engineering A,1998, A255:139-147.
[86] Miura H, Aoyama H, Sakai T. Effect of grain boundary misorientation on dynamicrecrystallization of Cu-Si bicrystals [J]. The Japan Institute of Metals,1994,58(3):267-275.
[87] McQueen H J. Development of dynamic recrystallization theory [J]. Materials Science andEngineering A,2004, A387:203-208.
[88] Perez-Prado MT, del Valle JA, Ruano OA. Effect of sheet thickness on the microstructuralevolution of an Mg AZ61alloy during large strain hot rolling [J]. Scripta Materialia,2004,50(5):667-671.
[89] Galiyev A, Kaibyshev R, Gottstein G. Grain refinement of ZK60magnesium alloy during lowtemperature deformation [J]. TMS Annual Meeting,2002,181-185.
[90] Galiyev A, Kaibyshev R. Microst ructural evolution in ZK60magnesium alloy during severeplastic deformation [J]. Materials Transactions,2001,42(7):1190-1199.
[91] Yang XY, Miura H, Sakai T. Isochronal Annealing Behavior of Magnesium Alloy AZ31afterHot Deformation [J]. Materials Transactions2005,46:2981-2987..
[92] Yang XY, Zhu YK, Miura H, Sakai T. Static recrystallization behavior of hot-deformedmagnesium alloy AZ31during isothermal annealing [J]. Transactions of Nonferrous MetalsSociety of China,2010,20:1269-1274.
[93] Yi SB, Schestakow I, Zaefferer S. Twinning-related microstructural evolution during hotrolling and subsequent annealing of pure magnesium [J]. Materials Science and EngineeringA,2009,516(1-2):58-64.
[94] Chao HY, Sun HF, Chen WZ, Wang ED. Static recrystallization kinetics of a heavily colddrawn AZ31magnesium alloy under annealing treatment [J]. Materials Characterization,2011,62:312-320.
[95] Bonarski BJ, Schafler E, Mingler B, Skrotzki W, Mikulowski B, Zehetbauer MJ. Textureevolution of Mg during high-pressure torsion [J]. Journal Materials Science,2008,43:7513-7518.
[96] Li X, Yang P, Wang LN, Meng L, Cui F. Orientational analysis of static recrystallization atcompression twins in a magnesium alloy AZ31[J]. Materials Science and Engineering A,2009,517:160-169.
[97] Wang YN, Huang JC. Texture analysis in hexagonal materials [J]. Materials Chemistry andPhysics,2003,81(1):11-26.
[98] Prado MT, Valle JA, Ruano OA.. Effect of sheet thickness on the microstructure evolution ofan Mg alloy during large strain hot rolling [J]. Scripta Materialia,2004,50(5):667-671.
[99] Yang P, Yu Y, Chen L, Mao W. Experimental determination and theoretical prediction of twinorientations in magnesium alloy AZ31[J]. Scripta Materialia,2004,50(8):1163-1168.
[100] Kalidindi SR. Incorporation of deformation twinning in crystal plasticity models [J]. Journalof the Mechanics and Physics of Solids,1998,46:267-290.
[101] Hilpert M, Styczynski A, Kiese J et al. Magnesium alloys and their application [M]. Hamburg:Werkstoff-informations gesellshaft,1998:319.
[102] Mukai T, Watanabe H, Ishikawa K, Higashi K. Guide for Enhancement of Room TemperatureDuctility in Mg Alloys at High Strain Rates [J]. Materials Science Forum,2003,(419-422):171-176.
[103] Masoudpanah SM, Mahmudi R. The microstructure, tensile, and shear deformation behaviorof an AZ31magnesium alloy after extrusion and equal channel angular pressing [J]. Materialsand Design,2010,31(7):3512-3517.
[104] Yu Y, Lawrence C, Shigeharu K. Effect of microstructural factors on tensile properties of anECAE-Processed AZ3I Magnesium alloy [J]. Materials Transactions,2003,44(4):468-475.
[105] Jahedi M, Paydar MH. Three-dimensional finite element analysis of torsion extrusion (TE) asan SPD process [J]. Materials Science and Engineering A,2011,528:8742-8749.
[106] Hu HJ, Zhang DF, Pan FS. Die structure optimization of equal channel angular extrusion forAZ31magnesium alloy based on finite element method [J]. Transactions of NonferrousMetals Society of China,2010,20(2):259-266.
[107] Hu HJ, Zhang DF, Pan FS, Yang MB, Zhang JP. Numerical and physical simulation of newSPD method combining extrusion and equal channel angular pressing for AZ31magnesiumalloy [J]. Transactions of Nonferrous Metals Society of China,2010,20(3):478-483.
[108] Ogawa N, Shiomi M, Osakada K. Forming Limit of Magnesium Alloy at ElevatedTemperatures for Precision Forging [J] International Journal of Machine Tools andManufacture,2002,42:607-614.
[109] Chandrasekaran M, Yong MSJ. Effect of Materials and Temperature on the Forward Extrusionof Magnesium Alloys [J]. Materials Science and Engineering A,2004, A381:308-319.
[110] Song JW, Han JW, Kim MS, Hwang SK. Fabrication of Magnesium Alloy AZ31Sheet byExtrusion [J]. Materials Science Forum,2004,449-452:65–68.
[111] Lapovok RY, Barnett MR, Davies CHJ. Construction of Extrusion Limit Diagram for AZ31Magnesium Alloy by FE Simulation [J]. Journal of Materials Processing Technology,2004,146:408-414.
[112] Fatemi-Varzaneh SM, Zarei-Hanzaki A, Naderi M, Roostaei AA. Deformation homogeneityin accumulative back extrusion processing of AZ31magnesium alloy [J]. Journal of alloysand compounds,2010,57(1):207-214.
[113] Liu G, Zhou J, Duszczyk J. Finite Element Simulation of Magnesium Extrusion toManufacture a Cross-Shaped Profile [J]. Journal of Manufacturing Science and Engineering,2007,129:607-614.
[114]于沪平，彭颖红，阮雪愉.平面分流焊合模成型过程的数值模拟[J].锻压技术，1999,24(5):9-11.
[115]吕炎等编著.精密塑性体积成形技术[M].北京：国防工业出版社,2003.
[116] Kim SI, Leen YS, Lee DL, Yoo YC. Modeling of AGS and recrystallized fraction ofmicroalloyed medium carbon steel during hot deformation [J]. Materials Science andEngineering A,2003,355(1-2):384-393.
[117] Mabuchi M, Asahina T, Iwasaki H, Higashi K. Experimental investigation of superplasticbehaviour in magnesium alloys [J]. Materials Science and Technology,1997,13:825-831.
[118] Iwahashi Y, Horita Z, Nemoto M, Langdon TG. The process of grain refinement inequal-channel angular pressing [J]. Acta Materialia,1998,46(9):3317-3331.
[119] Chung SW, Somekawa H, Kinoshita T, Kim WJ, Higashi K. The non-uniform behavior duringECAE process by3-D FVM simulation [J]. Scripta Materialia,2004,50(7):1079-1083.
[120] Djavanroodi F, EbrahimiM. Effect of die channel angle, friction and back pressure in theequal channel angular pressing using3D finite element simulation [J]. Materials Science andEngineering A,2010,527(4-5):1230-1235.
[121] Tang WQ, Huang SY, Zhang SR, Li DY, Peng YH. Influence of extrusion parameters ongrain size and texture distributions of AZ31alloy [J]. Journal of Materials ProcessingTechnology,2011,211(7):1203-1209.
[122] Ding SX, Chang CP, Kao PW. Effects of Processing Parameters on the Grain Refinement ofMagnesium Alloy by Equal-Channel Angular Extrusion [J]. Metallurgical and MaterialsTransactions A-physical Metallurgy and Materials Science,2009,40A (2):415-425.
[123] Xia K, Wang JT, Wu X, Chen G, Gurvan M. Equal channel angular pressing of magnesiumalloy AZ31[J]. Materials Science and Engineering A,2005,410–411:324–327.
[124] Jin L, Lin D, Mao D, Zeng X, Ding W. Mechanical properties and microstructure of AZ31Mgalloy processed by two-step equal channel angular extrusion [J]. Materials Letters,2005,59(18):2267-2270.
[125] Yoshida Y, Cisar L, Kamado S, Kojima Y. Effect of microstructural factors on tensileproperties of an ECAE-processed AZ31magnesium alloy [J]. Materials Transactions,2003,44(4):468-475.
[126] Yamashita A, Horita Z, Langdon TG. Improving the mechanical properties of magnesium anda magnesium alloy through severe plastic deformation [J]. Materials Science and EngineeringA,2001,300:142-147.
[127] Lapovok R, Thomson PF, Cottam R. The effect of grain refinement by warm equal channelangular extrusion on room temperature twinning in magnesium alloy ZK60[J]. Journal ofMaterials Science,2005,40:1699-1708.
[128] Xu SW, Zheng MY, Kamado S, Wu K, Wang GJ, Lv XY. Dynamic microstructural changesduring hot extrusion and mechanical properties of a Mg-5.0Zn-0.9Y-0.16Zr (wt.%) alloy [J].Materials Science and Engineering A,2011;528(12):4055-4067.
[129] Wu XX, Yang XY, Zhang L, Zhang ZL. Effect of Original Orientation on MicrostructureEvolution of AZ31Mg Alloy [J]. Acta Metallurgica Sinica,2011,47(2):140-144.
[130] Azeem MA, Tewarib A, Mishra S, Gollapudi S, Ramamurty U. Development of novel grainmorphology during hot extrusion of magnesium AZ21alloy [J]. Acta Materialia,2010,58(5):1495-1502.
[131] Hollomon JH. Tensile Deformation [J]. Trans A IME,1945,162:268-289.
[132] Ding SX, Lee WT, Chang CP, Chang LW, Kao PW. Improvement of strength of magnesiumalloy processed by equal channel angular extrusion [J]. Scripta Materialia,2008,59:1006–1009.
[133] Masoudpanaha SM, Mahmudi R. The microstructure, tensile, and shear deformation behaviorof an AZ31magnesium alloy after extrusion and equal channel angular pressing [J]. Materialsand Design,2010,31:3512-3517.
[134] Srinivasan M, Loganathan C, Balasubramanian V, Nguyen QB, Gupta M, Narayanasamy R.Feasibility of joining AZ31B magnesium metal matrix composite by friction welding [J].Materials and Design,2011,32:1672-1676.
[135] Nguyen QB, Gupta M. Enhancing mechanical response of AZ31B using Cu+nanoAl2O3addition [J]. Materials Science and Engineering A,2010,527:1411-1416.
[136] Nguyen QB, Gupta M. Microstructure and Mechanical Characteristics of AZ31B/Al2O3Nanocomposite with Addition of Ca [J]. Journal of Computational Materials,2009,43:5-17.
[137] Kim WJ, Lee JB, Kim WY, Jeong HT, Jeong HG. Microstructure and mechanical properties ofMg-Al-Zn alloy sheets severely deformed by asymmetrical rolling [J]. Scripta Materialia,2007,56(4)309-312.
[138]刘世宇. AZ31镁合金双侧变通道角挤压变形时组织性能与工艺的研究[D].重庆：重庆大学,2009.
[139] Eddahbi M, Perez P, Monge MA, Garces G, ParejaR, Adeva P. Microstructuralcharacterization of an extruded Mg-Ni-Y-RE alloy processed by equal channel angularextrusion [J]. Journal of Alloys and Compounds,2009,473(1-2):79-86.
[140] Tang WN, Chen RS, Zhou J, Han EH. Effect of ECAE temperature and billet orientation onthe microstructure, texture and mechanical properties of an extruded Mg-Zn-Y-Zr alloy [J].Materials Science and Engineering A,2009,499(1-2):404-410.
[141] Wu BL, Wan G, Zhang YD, Du XH, Wagner F, Esling C. Fragmentation of large grains inAZ31magnesium alloy during ECAE via route A [J]. Materials Science and Engineering A,2010,527(15)3365-3372.
[142] Lin HK, Huang JC, Langdon TG. Relationship between texture and low temperaturesuperplasticity in an extruded AZ31Mg alloy processed by ECAP [J]. Materials Scienceand Engineering A,2005,402(1-2)250-257.
[143] Su CW, Lu L, Lai MO. Mechanical behaviour and texture of annealed AZ31Mg alloydeformed by ECAP [J]. Materials Science and Technology,2007,23(3):290-296.
[144] Dalla Torre FH, Hanzi AC, Uggowitzer PJ. Microstructure and mechanical properties ofmicroalloyed and equal channel angular extruded Mg alloys [J]. Scripta Materialia,2008,59(2):207-210.
[145] Hu HJ, Zhang DF, Yang MB, DengM. Grain refinement in AZ31magnesium alloy rodfabricated by extrusion-shearing severe plastic deformation process [J]. Transactions ofNonferrous Metals Society of China,2011,21(2):243-249.
[146] Staroselsky.A, Anand.L. A constitutive model for hcp materials deforming by slip andtwinning：application to magnesium alloy AZ31B [J]. Internationsl Journal of Plasticity,2003,19(10):1843-1864.
[147] Ono.N, Rowak.R. Effect of deformation temperature on Hall-Petch relationship registered forpolycrystalline magnesium [J]. Materials Letters,2003,58:39-45.
[148] Al-Maharbi M, Karaman I, Beyerlein IJ, Foley D, Hartwig KT, Kecskes LJ, Mathaudhu SN.Microstructure, crystallographic texture, and plastic anisotropy evolution in an Mg alloyduring equal channel angular extrusion processing [J]. Materials Science and Engineering A,2011,528(25-26):7616-7627.
[149] Agnew SR, Horton JA, Lillo TM, Brown DW. Enhanced ductility in strongly texturedmagnesium produced by equal channel angular processing [J]. Scripta Materialia,2004,503(2):377-381.
[150] Suwas S, Gottstein G, Kumar R. Evolution of crystallographic texture during equal channelangular extrusion (ECAE) and its effects on secondary processing of magnesium [J].Materials Science and Engineering A,2007,471(1-2):1-14.
[151] Myshlyaev MM, McQueen HJ, Mwembela A et al. Twinning, dynamic recovery andrecrystallization in hot worked Mg-Al-Zn alloy [J]. Materials Science and Engineering A,2002,337:121-133.
[152] Miyazaki N. Dislocation density evaluation using dislocation kinetics model [J]. Journal ofCrystal Growth,2007,303:302-309.
[153]姜山. AZ31镁合金的变形行为及孪生机理研究[D].重庆：重庆大学,2010.
[154] Humphreys FJ, Ferry M. On the role of twinning in the Recrystallization of aluminium [J].Scripta Materialia,1996,35:99-105.
[155]张力,卢立伟,刘天模,李楠,孙朝勇.双向挤压后AZ31镁合金的微观组织与性能[J].重庆大学学报,2009,32:931-936.
[156]卢立伟. AZ31镁合金双向挤压变形的组织性能与工艺研究[D].重庆：重庆大学,2008.
[157] Biswas S, Dhinwal SS, Suwas S. Room Temperature Equal Channel Angular. Extrusion ofMagnesium [J]. Acta Materialia,2010,58:3247-3261.
[158]杨明波,潘复生,李忠盛,张静. Mg-Al系耐热镁合金中的合金元素及其作用[J].材料导报,2006,4:46-49.
[159]宋波,辛仁龙,刘庆.析出相对镁合金变形机理影响的研究进展[J].中国有色金属学报,2011,21:2719-2731.
[160] Clark JB. Transmission electron microscopy study of age hardening in a Mg-5wt.%Zn alloy[J]. Acta Metallurgica,1965,13:1281-1289.
[161] Clark JB. Age hardening in a Mg-9wt.%Al alloy [J]. Acta Metallurgica,1968,16:141-152.
[162] Chun JS, Byrne JG, Bornemann A. The inhibition of deformation twinning by precipitates ina magnesium-zinc alloy [J]. Philosophical Magazine,1969,20:291-300.
[163] Mukai T, Yamanoi M, H. Watanabe, Higashi K. Scr. Ductility enhancement In AZ31magnesium alloy by controlling its grain structure [J]. Scripta Materialia,2001,(45):89-94.
[164] Kaibyshev R, Shipilova K, Musin F, Motohashi Y. Continuous dynamic recrystallization inan Al–Li–Mg–Sc alloy during equal-channel angular extrusion [J]. Materials Science andEngineering A,2005,396:341-351.
[165] Beyerlein IJ, Lebensohn RA, Tome CN. Modeling texture and microstructural evolution inthe equal channel angular extrusion process [J]. Materials Science and Engineering A,2003,345:122-138.
[166]刘宇. AZ31镁合金变通道角挤压变形时组织性能与工艺的研究[D].重庆：重庆大学,2008.
[167] Shewmon PG. Trans. AIME1956,206:918.
[168] Frost HJ, Ashby ME. Deformation Mechanism Maps [M] Pergamon Press, Oxford,1982.
[169] Kim HK, Kim WJ. Microstructural instability and strength of an AZ31Mg alloy after severeplastic deformation [J]. Materials Science and Engineering A,2004,385(1-2):300-308.
[170] Prasad Y V R K, Rao K P. Effect of homogenization on the hot deformation behavior of castAZ31magnesium alloy [J]. Materials and Design,2009,30(9):3723-3730.
[171] Kaibyshev R, Sitdikov O. Dynamic recrystallization of magnesium at ambient temperature [J].Zeit schriftfur Metallkunde,1994,85:738-743.
[172] Reed-Hill RE, Robertson WD. Additional modes of deformation twinning in magnesium [J].Acta Metallurgica,1957,5:717–727.
[173] Liu JZ, Liu TM, Yuan HQ, Shi XL, Wang ZC. Effect of Cold Forging and StaticRecrystallization on Microstructure and Mechanical Property of Magnesium Alloy AZ31[J].Materials Transactions,2010,51:341-346.
[174] Yoo MH, Wei CT. Slip Modes of Hexagonal-Close-Packed Metals [J]. Journal of AppliedPhysics,1967,38:4317-4322.
[175] Wang YN, Huang JC. The role of twinning and untwinning in yielding behavior inhot-extruded Mg–Al–Zn alloy [J]. Acta Materialia,2007,55:897-905.
[176] Jiang S, Liu TM, ChenC, Jiang XQ. Law of Atomic Motion during {1011} Twinning inMagnesium Alloys [J]. Materials Transactions,2011,52(8):1585-1588.
[177] Lu LW, Liu TM, Chen Y, Wang LG, Wang ZC. Microstructure Evolution ofDual-Directional-Extruded Mg Alloy AZ31: An Experimental and Simulation Study [J].Materials Transactions,2010,51:2088–2093.
[178] Lu LW, Liu TM, Jiang S, Pan FS, Liu Q, Wang ZC. Microstructure and mechanical propertyof dual-directional-extruded Mg alloy AZ31[J]. Materials Science and Engineering A,2010,527:4050-4055.
[179] Chao HY, Yang Y, Wang X, Wang ED. Effect of grain size distribution and texture on thecold extrusion behavior and mechanical properties of AZ31Mg alloy [J]. Materials Scienceand Engineering A,2011,528:3428-3434.
[180] Martin E, Mishra RK, Jonas JJ. Effect of twinning on recrystallisation textures in deformedmagnesium alloy AZ31[J]. Philosophical Magazine,2011,91(27):3613-3626.
[181] Li X, Yang P, Meng L, Cui FE. Analysis of the Static Recrystallization at Tension Twins [J].Acta Metallurgica Sinica,2010,46(2):147-154.
[182] Wang SR, Kang SB, Cho J. Effect of hot compression and annealing on microstructureevolution of ZK60magnesium alloys [J]. Journal of Materials Science,2009,44(20):5475-5484.
[183] Martin E, Jiang L, Godet S, Jonas JJ. The combined effect of static recrystallization andtwinning on texture in magnesium alloys AM30and AZ31[J]. International Journal ofMaterials Research,2009,100(4):576-583.
[184] Thirumurugan M, Kumaran S, Suwas S, Rao TS. Effect of rolling temperature and reductionin thickness on microstructure and mechanical properties of ZM21magnesium alloy and itssubsequent annealing treatment [J]. Materials Science and Engineering A,2011,528(29-30):8460-8468.
[2] I. J. Polmear. Magnesium alloys and applications [J]. Materials Science and Technology,1994,10(2):1-16.
[3]陈振华,严红革,陈吉华.镁合金[M].北京:化学工业出版社,2004.
[4]刘正,张奎,曾小勤.镁基轻质合金理论基础及其应用[M].北京：机械工业出版社，2002.
[5]余琨,黎文献,王日初,等.变形镁合金的研究、开发和应用[J].中国有色金属学报,2003,13(2):277~288.
[6]崔昆.钢铁材料及有色金属材料[M].北京:机械工业出版社,1986.
[7] Elektron, Magnesium Alloys Handbook [M], Magnesium Elektron Ltd,1953.
[8]张津,章宗和,曾苏民等.镁合金及应用[M].北京:化学工业出版社，2004.
[9] Agnew S R O Z. Continuous, large strain, tension/compression testing of sheet material [J].International Journal of Plasticity,2005,(21):1161-1193.
[10] Taylor, G I. Plastic strain in metals [J]. Journal of the Institute of Metals,1938,(62):307-324.
[11] J. Jiang, A. Godfrey, W. Liu, et al. Microtexture evolution via deformation twinning and slipduring compression of magnesium alloy AZ31[J]. Materials Science and Engineering A,2008,(483–484):576–579.
[12] D. J. Bacon, V. Vitek. Atomic-scale modeling of dislocations and related properties in thehexagonal-close-packed metals [J]. Metallurgical and Materials Transactions,2002,33A:721-733.
[13] M.Mabuchi. Materials Transaction. Japan Institute of Metals,1995,36:1249-1254.
[14] M.R.Barnett, M.D.Nave, C.J.Bettles. Deformation microstructures and textures of some coldrolled Mg alloys [J]. Materials science and Engineering A,2004,(386):205-211.
[15] Perez-Prado.M.T, Del Valle.J.A. Microstructural Evolution During Large Strain Hot Rollingof an AM60Mg Alloy [J]. Scripta Materialia,2004,50(5):661-667.
[16] Chang.T.C, Wang.J.Y. Grain Refining of Magnesium Alloy AZ31by Rolling [J]. Journal ofMaterials Processing Technology,2003,140(3):588-593.
[17] Perez-prado.M.T, Del Valle.J.A, Ruano.O.A. Effect of Sheet Thickness on the MicrostructuralEvolution of an AZ61Mg Alloy during Large Strain Hot Rolling [J]. Scripta Materialia,2004,50(5):667-673.
[18]王新云，闫洪，胡国安等. AZ31变形镁合金挤压成形工艺研究[0]. http://www.paper.edu.cn.
[19] Murai.T, Matsuoka.S, Miyamoto.S. Effects of extrusion conditions on microstructure andmechanical properties of AZ31B magnesium alloy extrusions [J]. Journal of MaterialsProcessing Technology,2003,141(2):207-215.
[20] Lapovok.R.Y, Barnett.M.R, Davies.C.H.J. Construction of extrusion limit diagram for AZ31magnesium alloy by FE simulation [J]. Journal of Materials Processing Technology,2004,146(3):408-413.
[21] Kleiner.S, Uggowitzer.P.J. Mechanical anisotropy of extruded Mg-6%Al-1%Zn alloy [J].Materials Science and Engineering A.,2004,(379):258-267.
[22] Ogawa.N, Shiomi.M, Osakakd. Forming limit of magnesium alloy at elevated temperaturesfor precision forging [J]. International Journal of Machine tools&manufacture,2002,(42):607-614.
[23]张士宏,王忠堂.镁合金的塑性加工工艺[J].金属成形工艺,2002,20(5):1-3.
[24] Aghion E, Eliezer D. Magnesium and magnesium alloys-Science, Technology andApplication [M]. Israel: Avi moshe Bregman Ltd,2004.
[25] Shan DB, Xu WC, Lu Y. Study on precision forging technology for a complex-shaped lightalloy forging [J]. Journal of Materials Processing Technology,2004,(151):289-293.
[26] Kawasaki M, Langdon TG. Principles of superplasticity in ultrafine-grained materials [J].Journal of Materials Science,2007,42:1782-1796.
[27] Figueiredo RB, Langdon TG. Strategies for achieving high strain rate superplasticity inmagnesium alloys processed by equal-channel angular pressing [J]. Scripta Materialia.2009,61(1):84-87.
[28] Watanabe.H, Mukai.T, Ishikawa.K. High-strain-rate superplasticity at low temperature in aZK61magnesium alloy produced by power metallurgy [J]. Scripta Materialia,1999,41(2):209-213.
[29] Watanabe.H, Mukai.T, Ishikawa.K, Higashi.K. High-strain-rate superplasticity in an AZ91magnesium alloy processed by ingot metallurgy route [J]. Materials Transactions,2002,43(1):78-93.
[30] Watanabe.H, Mukai.T, Ishikawa.K. Superplasticity of a particle-strengthened WE43magnesium alloy [J]. Materials Transactions,2001,42(1):157-163.
[31]洪慎章.冷挤压技术[M].北京：机械工业出版社，2005.
[32] Ravi Kumar NV, Blandin JJ, Desra YCet al. Grain refinement in AZ91magnesium alloyduring thermomechanical processing [J]. Materials Science and Engineering A,2003,359(1-2):150-157.
[33] Figueiredo RB, Langdon TG. Grain refinement and mechanical behavior of a magnesiumalloy processed by ECAP [J]. Journal of Materials Science,2010,45:4827-4836.
[34] Shahzad M, Wagner L. Influence of extrusion parameters on microstructure and texturedevelopments, and their effects on mechanical properties of the magnesium alloy AZ80[J].Materials Science and Engineering A,2009,506(1-2):141-147.
[35] El-Morsy A., Ismail A, Waly M. Microstructural and mechanical properties evolution ofmagnesium AZ61alloy processed through a combination of extrusion and thermomechanicalprocesses [J]. Materials Science and Engineering A,2008,486(1-2):528-533.
[36] Beer AG， Bamett MR. The influence of twinning on the hot working flow stress andmicrostructural evolution of magnesium alloy AZ31[J]. Materials Science Forum,2005,488-489:611-614.
[37]张广俊，龙思远，曹凤红. AZ81镁合金挤压组织和性能研究[J].材料导报，2008,22:381-383.
[38]石磊，李继文，李永兵等. AZ31镁合金热挤压变形和力学性能分析[J].锻压技术，2009,34(6):35-38.
[39]陈国清，宋军辉，付雪松等.连铸AZ31镁合金的热挤压变形组织和性能[J].塑性工程学报，2009,16(6):50-55.
[40]胡燕辉，李建国，谭敦强.坯料细化处理对AZ31镁合金挤压组织的影响[J].轻合金加工技术，2010,38(3):42-46.
[41]尹从娟，张星，张治民.热挤压工艺对AZ31镁合金组织性能的影响[J].热加工工艺，2007,36(21):63-67.
[42]曲家惠，岳明凯，黄涛. AZ31镁合金在不同挤压比和挤压温度下的织构演变[J].沈阳理工大学学报，2009,28(2):48-51.
[43] Segal V M, Reznikov V I. Plastic working of metals by simple shear [J]. Russian Metallugy,1981,1:99-105.
[44] Kaibyshev R, Mazurina I. Mechanisms of grain refinement in aluminum alloys during severeplastic deformation [J]. Materials Science Forum,2004,467-470:1251-1260.
[45] Segal V M. Equal channel angular extrusion: from macromechanics to structure formation [J].Materials Science and Engineering A,1999,271(1-2):322-333.
[46] Mabuchi M, Iwasaki H, Yanase K, Higashi K. Low temperature superplasticity in an AZ91magnesium alloy processed by ECAE [J]. Scripta Materialia,1997,36(6):681-686.
[47] Wu D, Chen RS, Han EH. Bonding interface zone of Mg-Gd-Y/Mg-Zn-Gd laminatedcomposite fabricated by equal channel angular extrusion [J]. Transactions of NonferrousMetals Society of China,2010,20: S613-S618.
[48] Liu XB, Chen RS, Han EH. Preliminary investigations on the Mg-Al-Zn/Al laminatedcomposite fabricated by equal channel angular extrusion [J]. Journal of Materials ProcessingTechnology,2009,209(10):4675-4681.
[49] Song D, Ma AB, Jiang JH, Lin PH, Yang DH, Fan JF. Corrosion behaviour of bulk ultra-finegrained AZ91D magnesium alloy fabricated by equal-channel angular pressing [J]. CorrosionScience,2011,53(1):362-373.
[50] Birbilis N, Ralston KD, Virtanen S, Fraser HL, Davies CHJ. Grain character influences oncorrosion of ECAPed pure magnesium [J]. Corrosion Engineering Science and Technology,2010,45(3):224-230.
[51] Zhao ZD, ChenQA, Chao HY, Hu CK, Huang SH. Influence of equal channel angularextrusion processing parameters on the microstructure and mechanical properties ofMg-Al-Y-Zn alloy [J]. Materials and Design,2011,32(2):575-583.
[52] Segal V M. Slip line solutions, deformation mode and loading history during equal channelangular extrusion [J]. Materials Science and Engineering A,2003,345(1-2):36-46.
[53]杜忠泽,冯广海,符寒光,王经涛,赵西成. ECAP变形与材料组织性能控制的研究[J].材料工程,2006(3):64-68.
[54] Wang QD, Chen YJ, Lin JB, Zhang LJ, Zhai CQ. Microstructure and properties of magnesiumalloy processed by a new severe plastic deformation method [J]. Materials Letters,2007,61(23-24):4599-4602.
[55] Jahedi M, Paydar MH. Three-dimensional finite element analysis of torsion extrusion (TE) asan SPD process [J]. Materials Science and Engineering A,2011,528(29-30):8742-8749.
[56] Azushima A, Aoki K. Properties of Ultrafine-grained Steel by Repeated Shear Deformation ofSide Extrusion Process [J]. Materials Science and Engineering A,2002,377(1–2):45–49.
[57] Azushima A, Aoki K, Inoue T. Properties of Ultra Low Carbon Steel Produced by RepetitiveShear Deformation of Side Extrusion [J]. Tetsu to Hagane,2001,87(12):762–766.
[58] Aoki K, Kimura Y, Asada Y, Azushima A. Creation ofHigh Strength Carbon Steels byRepetitive Shear Deformation Process and Heat Treatment [J]. Proceedings of the7thInternational Conference on Technology of Plasticity,2002,1195-1200.
[59] Nakashima K, Horita Z, Nemoto M, Langdon TG. Development of a Multi-pass Facility forEqual-channel Angular Pressing to High Total Strains [J]. Materials Science and EngineeringA,2000,281(1-2):82-87.
[60] Liu ZY, Liang GX, Wang ED, Wang ZR. The Effect of Cumulative Large Plastic Strain on theStructure and Properties of a Cu–Zn Alloy [J]. Materials Science and Engineering A,1998,242(1-2):137-140.
[61] Ono M, Mizufune H, Narita M. Development of Semi-Continuous4Stage ECAE Method [J].Proceedings of the7th International Conference on Technology of Plasticity, Yokohama,2002,1249-1254.
[62] Rosochowski A, Olejnik L. Numerical and Physical Modeling of Plastic Deformation in2-turn Equal Channel Angular Extrusion [J]. Journal of Materials Processing Technology,2002,125-126:309-316.
[63] Rosochowski A, Rodiet R, Lipinski P. Finite Element Simulation of CyclicExtrusion-compression [J]. Proceedings of the8th International Conference on MetalForming Krakow,2000,3-7,2530-3259.
[64] Richert M, McQueen HJ, Richert J. Microband Formation in Cyclic Extrusion Compressionof Aluminum [J]. Canadian Metallurgical Quarterly,1998,37(5):449-457.
[65] Richert M, Liu Q, Hansen N. Microstructural Evolution Over A Large Strain Range inAluminium Deformed by Cyclic-Extrusion–Compression[J]. Materials Science andEngineering A,1999,268(1-2):275-283.
[66] Aizawa T, Katsuzawa K, Kihara J. Mechano-Metallurgical Processing for Direct Fabricationof Solid Non-equilibrium Phase [J]. Faculty of Engineering University of Tokyo Series B,1993,42(3):261-279.
[67] Neugebauer R, Glass R, Hoffmann M, Putz M. Spin Extrusion—A New Partial FormingTechnology based on7NC-Axes Machining [J]. CIRP Annals,2005,54(1):241-244.
[68] Ha11EO.The deformation and ageing of mild steel: III discussion of results [J]. Proceedingsof the Physical Society of London,1951,(64):747-753.
[69] Petch NJ. The cleavage strength of polycrystals [J]. Journal of the Iron and Steel Institute,1953,(174):25-28.
[70] Kim WJ, Hong SI, Kim YS. Texture development and its effect on mechanical properties ofan AZ61Mg alloy fabricated by equal channel angular pressing [J]. Acta Materialia,2003,(51):3293-3307.
[71]佐藤雅彦,薄板压延.秘制造工程诸特性[J].轻金属,2004,11:465.
[72] Kim HK, Kim WJ. Microstructural instability and strength of an AZ31Mg alloy after severeplastic deformation [J]. Materials Science and Engineering A,2004,385(1-2):300-308.
[73] Lu LW, Liu TM, Chen Y, Wang LG, Wang ZC. Double Change Channel Angular Pressing ofMagnesium Alloys AZ31[J]. Materials and Design,2012,35:138-143
[74] Lu LW, Liu TM, Jiang S, Pan FS, Liu Q, Wang ZC. Microstructure and mechanical propertyof dual-directional-extruded Mg alloy AZ31[J]. Materials Science and Engineering A,2010,527:4050–4055.
[75] Rao KP, Prasad YVRK, Suresh K. Materials modeling and simulation of isothermal forging ofrolled AZ31B magnesium alloy: Anisotropy of flow [J]. Materials and Design,2011,32:2545-2553.
[76] Das S, Lim NS, Seol JB, Kim HW, Park CG. Effect of the rolling speed on microstructuraland mechanical properties of aluminum-magnesium alloys prepared by twin roll casting [J].Materials and Design,2010,31:1633-1638.
[77] Gong XB, Li H, Suk BK, Cho JH, Li S. Microstructure and mechanical properties of twin-rollcast Mg–4.5Al–1.0Zn sheets processed by differential speed rolling [J]. Materials and Design,2010,31:1581-1587.
[78] Masoudpanah SM, Mahmudi R. The microstructure, tensile, and shear deformation behaviorof an AZ31magnesium alloy after extrusion and equal channel angular pressing [J]. Mater-ials and Design,2010,31:3512-3517.
[79] Ion SE, Humphreys FJ, White SH. Dynamic recrystallisation and the development of microstructure during the high temperature deformation of magnesium [J]. Acta Metallurgica,1982,30:1909-1919.
[80]刘楚明，刘子娟，朱秀荣，周海涛.镁及镁合金动态再结晶研究进展[J].中国有色金属学报，2006,16(1):1-12.
[81] Igarashi M, Khantha M, Vitek V. N-body inter-atomic potentials for hexagonal close-packedmetals [J]. Philosophical Magazine B,1991,63(3):603-627.
[82] Gourdet S, Montheillet F. A model of continuous dynamic recrystallization [J]. ActaMaterialia,2003,51:26852699.
[83]周海涛. AZ61镁合金高温塑性变形行为及管材热挤压研究[D].上海：上海交通大学,2004.
[84] Galiyev A, Kaibyshev R, Gottstein G. Correlation of plastic deformation and dynamicrecrystallization in magnesium alloy ZK60[J]. Acta Materialia,2001,49:1199-1207.
[85] Belyakov A, Miura H, Sakai T. Dynamic recrystallization under warm deformation of a304type austenitic stainless steel [J]. Materials Science and Engineering A,1998, A255:139-147.
[86] Miura H, Aoyama H, Sakai T. Effect of grain boundary misorientation on dynamicrecrystallization of Cu-Si bicrystals [J]. The Japan Institute of Metals,1994,58(3):267-275.
[87] McQueen H J. Development of dynamic recrystallization theory [J]. Materials Science andEngineering A,2004, A387:203-208.
[88] Perez-Prado MT, del Valle JA, Ruano OA. Effect of sheet thickness on the microstructuralevolution of an Mg AZ61alloy during large strain hot rolling [J]. Scripta Materialia,2004,50(5):667-671.
[89] Galiyev A, Kaibyshev R, Gottstein G. Grain refinement of ZK60magnesium alloy during lowtemperature deformation [J]. TMS Annual Meeting,2002,181-185.
[90] Galiyev A, Kaibyshev R. Microst ructural evolution in ZK60magnesium alloy during severeplastic deformation [J]. Materials Transactions,2001,42(7):1190-1199.
[91] Yang XY, Miura H, Sakai T. Isochronal Annealing Behavior of Magnesium Alloy AZ31afterHot Deformation [J]. Materials Transactions2005,46:2981-2987..
[92] Yang XY, Zhu YK, Miura H, Sakai T. Static recrystallization behavior of hot-deformedmagnesium alloy AZ31during isothermal annealing [J]. Transactions of Nonferrous MetalsSociety of China,2010,20:1269-1274.
[93] Yi SB, Schestakow I, Zaefferer S. Twinning-related microstructural evolution during hotrolling and subsequent annealing of pure magnesium [J]. Materials Science and EngineeringA,2009,516(1-2):58-64.
[94] Chao HY, Sun HF, Chen WZ, Wang ED. Static recrystallization kinetics of a heavily colddrawn AZ31magnesium alloy under annealing treatment [J]. Materials Characterization,2011,62:312-320.
[95] Bonarski BJ, Schafler E, Mingler B, Skrotzki W, Mikulowski B, Zehetbauer MJ. Textureevolution of Mg during high-pressure torsion [J]. Journal Materials Science,2008,43:7513-7518.
[96] Li X, Yang P, Wang LN, Meng L, Cui F. Orientational analysis of static recrystallization atcompression twins in a magnesium alloy AZ31[J]. Materials Science and Engineering A,2009,517:160-169.
[97] Wang YN, Huang JC. Texture analysis in hexagonal materials [J]. Materials Chemistry andPhysics,2003,81(1):11-26.
[98] Prado MT, Valle JA, Ruano OA.. Effect of sheet thickness on the microstructure evolution ofan Mg alloy during large strain hot rolling [J]. Scripta Materialia,2004,50(5):667-671.
[99] Yang P, Yu Y, Chen L, Mao W. Experimental determination and theoretical prediction of twinorientations in magnesium alloy AZ31[J]. Scripta Materialia,2004,50(8):1163-1168.
[100] Kalidindi SR. Incorporation of deformation twinning in crystal plasticity models [J]. Journalof the Mechanics and Physics of Solids,1998,46:267-290.
[101] Hilpert M, Styczynski A, Kiese J et al. Magnesium alloys and their application [M]. Hamburg:Werkstoff-informations gesellshaft,1998:319.
[102] Mukai T, Watanabe H, Ishikawa K, Higashi K. Guide for Enhancement of Room TemperatureDuctility in Mg Alloys at High Strain Rates [J]. Materials Science Forum,2003,(419-422):171-176.
[103] Masoudpanah SM, Mahmudi R. The microstructure, tensile, and shear deformation behaviorof an AZ31magnesium alloy after extrusion and equal channel angular pressing [J]. Materialsand Design,2010,31(7):3512-3517.
[104] Yu Y, Lawrence C, Shigeharu K. Effect of microstructural factors on tensile properties of anECAE-Processed AZ3I Magnesium alloy [J]. Materials Transactions,2003,44(4):468-475.
[105] Jahedi M, Paydar MH. Three-dimensional finite element analysis of torsion extrusion (TE) asan SPD process [J]. Materials Science and Engineering A,2011,528:8742-8749.
[106] Hu HJ, Zhang DF, Pan FS. Die structure optimization of equal channel angular extrusion forAZ31magnesium alloy based on finite element method [J]. Transactions of NonferrousMetals Society of China,2010,20(2):259-266.
[107] Hu HJ, Zhang DF, Pan FS, Yang MB, Zhang JP. Numerical and physical simulation of newSPD method combining extrusion and equal channel angular pressing for AZ31magnesiumalloy [J]. Transactions of Nonferrous Metals Society of China,2010,20(3):478-483.
[108] Ogawa N, Shiomi M, Osakada K. Forming Limit of Magnesium Alloy at ElevatedTemperatures for Precision Forging [J] International Journal of Machine Tools andManufacture,2002,42:607-614.
[109] Chandrasekaran M, Yong MSJ. Effect of Materials and Temperature on the Forward Extrusionof Magnesium Alloys [J]. Materials Science and Engineering A,2004, A381:308-319.
[110] Song JW, Han JW, Kim MS, Hwang SK. Fabrication of Magnesium Alloy AZ31Sheet byExtrusion [J]. Materials Science Forum,2004,449-452:65–68.
[111] Lapovok RY, Barnett MR, Davies CHJ. Construction of Extrusion Limit Diagram for AZ31Magnesium Alloy by FE Simulation [J]. Journal of Materials Processing Technology,2004,146:408-414.
[112] Fatemi-Varzaneh SM, Zarei-Hanzaki A, Naderi M, Roostaei AA. Deformation homogeneityin accumulative back extrusion processing of AZ31magnesium alloy [J]. Journal of alloysand compounds,2010,57(1):207-214.
[113] Liu G, Zhou J, Duszczyk J. Finite Element Simulation of Magnesium Extrusion toManufacture a Cross-Shaped Profile [J]. Journal of Manufacturing Science and Engineering,2007,129:607-614.
[114]于沪平，彭颖红，阮雪愉.平面分流焊合模成型过程的数值模拟[J].锻压技术，1999,24(5):9-11.
[115]吕炎等编著.精密塑性体积成形技术[M].北京：国防工业出版社,2003.
[116] Kim SI, Leen YS, Lee DL, Yoo YC. Modeling of AGS and recrystallized fraction ofmicroalloyed medium carbon steel during hot deformation [J]. Materials Science andEngineering A,2003,355(1-2):384-393.
[117] Mabuchi M, Asahina T, Iwasaki H, Higashi K. Experimental investigation of superplasticbehaviour in magnesium alloys [J]. Materials Science and Technology,1997,13:825-831.
[118] Iwahashi Y, Horita Z, Nemoto M, Langdon TG. The process of grain refinement inequal-channel angular pressing [J]. Acta Materialia,1998,46(9):3317-3331.
[119] Chung SW, Somekawa H, Kinoshita T, Kim WJ, Higashi K. The non-uniform behavior duringECAE process by3-D FVM simulation [J]. Scripta Materialia,2004,50(7):1079-1083.
[120] Djavanroodi F, EbrahimiM. Effect of die channel angle, friction and back pressure in theequal channel angular pressing using3D finite element simulation [J]. Materials Science andEngineering A,2010,527(4-5):1230-1235.
[121] Tang WQ, Huang SY, Zhang SR, Li DY, Peng YH. Influence of extrusion parameters ongrain size and texture distributions of AZ31alloy [J]. Journal of Materials ProcessingTechnology,2011,211(7):1203-1209.
[122] Ding SX, Chang CP, Kao PW. Effects of Processing Parameters on the Grain Refinement ofMagnesium Alloy by Equal-Channel Angular Extrusion [J]. Metallurgical and MaterialsTransactions A-physical Metallurgy and Materials Science,2009,40A (2):415-425.
[123] Xia K, Wang JT, Wu X, Chen G, Gurvan M. Equal channel angular pressing of magnesiumalloy AZ31[J]. Materials Science and Engineering A,2005,410–411:324–327.
[124] Jin L, Lin D, Mao D, Zeng X, Ding W. Mechanical properties and microstructure of AZ31Mgalloy processed by two-step equal channel angular extrusion [J]. Materials Letters,2005,59(18):2267-2270.
[125] Yoshida Y, Cisar L, Kamado S, Kojima Y. Effect of microstructural factors on tensileproperties of an ECAE-processed AZ31magnesium alloy [J]. Materials Transactions,2003,44(4):468-475.
[126] Yamashita A, Horita Z, Langdon TG. Improving the mechanical properties of magnesium anda magnesium alloy through severe plastic deformation [J]. Materials Science and EngineeringA,2001,300:142-147.
[127] Lapovok R, Thomson PF, Cottam R. The effect of grain refinement by warm equal channelangular extrusion on room temperature twinning in magnesium alloy ZK60[J]. Journal ofMaterials Science,2005,40:1699-1708.
[128] Xu SW, Zheng MY, Kamado S, Wu K, Wang GJ, Lv XY. Dynamic microstructural changesduring hot extrusion and mechanical properties of a Mg-5.0Zn-0.9Y-0.16Zr (wt.%) alloy [J].Materials Science and Engineering A,2011;528(12):4055-4067.
[129] Wu XX, Yang XY, Zhang L, Zhang ZL. Effect of Original Orientation on MicrostructureEvolution of AZ31Mg Alloy [J]. Acta Metallurgica Sinica,2011,47(2):140-144.
[130] Azeem MA, Tewarib A, Mishra S, Gollapudi S, Ramamurty U. Development of novel grainmorphology during hot extrusion of magnesium AZ21alloy [J]. Acta Materialia,2010,58(5):1495-1502.
[131] Hollomon JH. Tensile Deformation [J]. Trans A IME,1945,162:268-289.
[132] Ding SX, Lee WT, Chang CP, Chang LW, Kao PW. Improvement of strength of magnesiumalloy processed by equal channel angular extrusion [J]. Scripta Materialia,2008,59:1006–1009.
[133] Masoudpanaha SM, Mahmudi R. The microstructure, tensile, and shear deformation behaviorof an AZ31magnesium alloy after extrusion and equal channel angular pressing [J]. Materialsand Design,2010,31:3512-3517.
[134] Srinivasan M, Loganathan C, Balasubramanian V, Nguyen QB, Gupta M, Narayanasamy R.Feasibility of joining AZ31B magnesium metal matrix composite by friction welding [J].Materials and Design,2011,32:1672-1676.
[135] Nguyen QB, Gupta M. Enhancing mechanical response of AZ31B using Cu+nanoAl2O3addition [J]. Materials Science and Engineering A,2010,527:1411-1416.
[136] Nguyen QB, Gupta M. Microstructure and Mechanical Characteristics of AZ31B/Al2O3Nanocomposite with Addition of Ca [J]. Journal of Computational Materials,2009,43:5-17.
[137] Kim WJ, Lee JB, Kim WY, Jeong HT, Jeong HG. Microstructure and mechanical properties ofMg-Al-Zn alloy sheets severely deformed by asymmetrical rolling [J]. Scripta Materialia,2007,56(4)309-312.
[138]刘世宇. AZ31镁合金双侧变通道角挤压变形时组织性能与工艺的研究[D].重庆：重庆大学,2009.
[139] Eddahbi M, Perez P, Monge MA, Garces G, ParejaR, Adeva P. Microstructuralcharacterization of an extruded Mg-Ni-Y-RE alloy processed by equal channel angularextrusion [J]. Journal of Alloys and Compounds,2009,473(1-2):79-86.
[140] Tang WN, Chen RS, Zhou J, Han EH. Effect of ECAE temperature and billet orientation onthe microstructure, texture and mechanical properties of an extruded Mg-Zn-Y-Zr alloy [J].Materials Science and Engineering A,2009,499(1-2):404-410.
[141] Wu BL, Wan G, Zhang YD, Du XH, Wagner F, Esling C. Fragmentation of large grains inAZ31magnesium alloy during ECAE via route A [J]. Materials Science and Engineering A,2010,527(15)3365-3372.
[142] Lin HK, Huang JC, Langdon TG. Relationship between texture and low temperaturesuperplasticity in an extruded AZ31Mg alloy processed by ECAP [J]. Materials Scienceand Engineering A,2005,402(1-2)250-257.
[143] Su CW, Lu L, Lai MO. Mechanical behaviour and texture of annealed AZ31Mg alloydeformed by ECAP [J]. Materials Science and Technology,2007,23(3):290-296.
[144] Dalla Torre FH, Hanzi AC, Uggowitzer PJ. Microstructure and mechanical properties ofmicroalloyed and equal channel angular extruded Mg alloys [J]. Scripta Materialia,2008,59(2):207-210.
[145] Hu HJ, Zhang DF, Yang MB, DengM. Grain refinement in AZ31magnesium alloy rodfabricated by extrusion-shearing severe plastic deformation process [J]. Transactions ofNonferrous Metals Society of China,2011,21(2):243-249.
[146] Staroselsky.A, Anand.L. A constitutive model for hcp materials deforming by slip andtwinning：application to magnesium alloy AZ31B [J]. Internationsl Journal of Plasticity,2003,19(10):1843-1864.
[147] Ono.N, Rowak.R. Effect of deformation temperature on Hall-Petch relationship registered forpolycrystalline magnesium [J]. Materials Letters,2003,58:39-45.
[148] Al-Maharbi M, Karaman I, Beyerlein IJ, Foley D, Hartwig KT, Kecskes LJ, Mathaudhu SN.Microstructure, crystallographic texture, and plastic anisotropy evolution in an Mg alloyduring equal channel angular extrusion processing [J]. Materials Science and Engineering A,2011,528(25-26):7616-7627.
[149] Agnew SR, Horton JA, Lillo TM, Brown DW. Enhanced ductility in strongly texturedmagnesium produced by equal channel angular processing [J]. Scripta Materialia,2004,503(2):377-381.
[150] Suwas S, Gottstein G, Kumar R. Evolution of crystallographic texture during equal channelangular extrusion (ECAE) and its effects on secondary processing of magnesium [J].Materials Science and Engineering A,2007,471(1-2):1-14.
[151] Myshlyaev MM, McQueen HJ, Mwembela A et al. Twinning, dynamic recovery andrecrystallization in hot worked Mg-Al-Zn alloy [J]. Materials Science and Engineering A,2002,337:121-133.
[152] Miyazaki N. Dislocation density evaluation using dislocation kinetics model [J]. Journal ofCrystal Growth,2007,303:302-309.
[153]姜山. AZ31镁合金的变形行为及孪生机理研究[D].重庆：重庆大学,2010.
[154] Humphreys FJ, Ferry M. On the role of twinning in the Recrystallization of aluminium [J].Scripta Materialia,1996,35:99-105.
[155]张力,卢立伟,刘天模,李楠,孙朝勇.双向挤压后AZ31镁合金的微观组织与性能[J].重庆大学学报,2009,32:931-936.
[156]卢立伟. AZ31镁合金双向挤压变形的组织性能与工艺研究[D].重庆：重庆大学,2008.
[157] Biswas S, Dhinwal SS, Suwas S. Room Temperature Equal Channel Angular. Extrusion ofMagnesium [J]. Acta Materialia,2010,58:3247-3261.
[158]杨明波,潘复生,李忠盛,张静. Mg-Al系耐热镁合金中的合金元素及其作用[J].材料导报,2006,4:46-49.
[159]宋波,辛仁龙,刘庆.析出相对镁合金变形机理影响的研究进展[J].中国有色金属学报,2011,21:2719-2731.
[160] Clark JB. Transmission electron microscopy study of age hardening in a Mg-5wt.%Zn alloy[J]. Acta Metallurgica,1965,13:1281-1289.
[161] Clark JB. Age hardening in a Mg-9wt.%Al alloy [J]. Acta Metallurgica,1968,16:141-152.
[162] Chun JS, Byrne JG, Bornemann A. The inhibition of deformation twinning by precipitates ina magnesium-zinc alloy [J]. Philosophical Magazine,1969,20:291-300.
[163] Mukai T, Yamanoi M, H. Watanabe, Higashi K. Scr. Ductility enhancement In AZ31magnesium alloy by controlling its grain structure [J]. Scripta Materialia,2001,(45):89-94.
[164] Kaibyshev R, Shipilova K, Musin F, Motohashi Y. Continuous dynamic recrystallization inan Al–Li–Mg–Sc alloy during equal-channel angular extrusion [J]. Materials Science andEngineering A,2005,396:341-351.
[165] Beyerlein IJ, Lebensohn RA, Tome CN. Modeling texture and microstructural evolution inthe equal channel angular extrusion process [J]. Materials Science and Engineering A,2003,345:122-138.
[166]刘宇. AZ31镁合金变通道角挤压变形时组织性能与工艺的研究[D].重庆：重庆大学,2008.
[167] Shewmon PG. Trans. AIME1956,206:918.
[168] Frost HJ, Ashby ME. Deformation Mechanism Maps [M] Pergamon Press, Oxford,1982.
[169] Kim HK, Kim WJ. Microstructural instability and strength of an AZ31Mg alloy after severeplastic deformation [J]. Materials Science and Engineering A,2004,385(1-2):300-308.
[170] Prasad Y V R K, Rao K P. Effect of homogenization on the hot deformation behavior of castAZ31magnesium alloy [J]. Materials and Design,2009,30(9):3723-3730.
[171] Kaibyshev R, Sitdikov O. Dynamic recrystallization of magnesium at ambient temperature [J].Zeit schriftfur Metallkunde,1994,85:738-743.
[172] Reed-Hill RE, Robertson WD. Additional modes of deformation twinning in magnesium [J].Acta Metallurgica,1957,5:717–727.
[173] Liu JZ, Liu TM, Yuan HQ, Shi XL, Wang ZC. Effect of Cold Forging and StaticRecrystallization on Microstructure and Mechanical Property of Magnesium Alloy AZ31[J].Materials Transactions,2010,51:341-346.
[174] Yoo MH, Wei CT. Slip Modes of Hexagonal-Close-Packed Metals [J]. Journal of AppliedPhysics,1967,38:4317-4322.
[175] Wang YN, Huang JC. The role of twinning and untwinning in yielding behavior inhot-extruded Mg–Al–Zn alloy [J]. Acta Materialia,2007,55:897-905.
[176] Jiang S, Liu TM, ChenC, Jiang XQ. Law of Atomic Motion during {1011} Twinning inMagnesium Alloys [J]. Materials Transactions,2011,52(8):1585-1588.
[177] Lu LW, Liu TM, Chen Y, Wang LG, Wang ZC. Microstructure Evolution ofDual-Directional-Extruded Mg Alloy AZ31: An Experimental and Simulation Study [J].Materials Transactions,2010,51:2088–2093.
[178] Lu LW, Liu TM, Jiang S, Pan FS, Liu Q, Wang ZC. Microstructure and mechanical propertyof dual-directional-extruded Mg alloy AZ31[J]. Materials Science and Engineering A,2010,527:4050-4055.
[179] Chao HY, Yang Y, Wang X, Wang ED. Effect of grain size distribution and texture on thecold extrusion behavior and mechanical properties of AZ31Mg alloy [J]. Materials Scienceand Engineering A,2011,528:3428-3434.
[180] Martin E, Mishra RK, Jonas JJ. Effect of twinning on recrystallisation textures in deformedmagnesium alloy AZ31[J]. Philosophical Magazine,2011,91(27):3613-3626.
[181] Li X, Yang P, Meng L, Cui FE. Analysis of the Static Recrystallization at Tension Twins [J].Acta Metallurgica Sinica,2010,46(2):147-154.
[182] Wang SR, Kang SB, Cho J. Effect of hot compression and annealing on microstructureevolution of ZK60magnesium alloys [J]. Journal of Materials Science,2009,44(20):5475-5484.
[183] Martin E, Jiang L, Godet S, Jonas JJ. The combined effect of static recrystallization andtwinning on texture in magnesium alloys AM30and AZ31[J]. International Journal ofMaterials Research,2009,100(4):576-583.
[184] Thirumurugan M, Kumaran S, Suwas S, Rao TS. Effect of rolling temperature and reductionin thickness on microstructure and mechanical properties of ZM21magnesium alloy and itssubsequent annealing treatment [J]. Materials Science and Engineering A,2011,528(29-30):8460-8468.
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