用户名: 密码: 验证码:
不同取向镍基单晶合金的蠕变行为与微观变形机制
详细信息    本馆镜像全文|  推荐本文 |  |   获取CNKI官网全文
摘要
本文通过测定[001]、[011]以及[111]取向单晶合金在不同条件下的蠕变曲线及组织形貌观察,研究了不同取向单晶合金的蠕变行为及微观变形机制,得出以下结论:
     [001]取向单晶合金的横断面枝晶呈现整齐的“+”字花样;[011]取向合金在横截面沿垂直方向的枝晶尺寸较长,沿水平方向的枝晶尺寸较短;而[111]取向的二次枝晶呈60°、或120°夹角分布。[001]、[011]和[111]取向单晶合金经完全热处理后,其组织结构均是立方γ′相沿<100>取向规则排列,其中,[011]取向合金中立方γ′相在(100)晶面呈45o角排列,经高温蠕变后,γ′相在三维空间沿<100>特定取向形成纤维状筏形组织,其γ基体相连续填充在筏状γ′相之间。[111]取向合金经高温蠕变后,γ′相在(?101)晶面沿与[111]应力轴方向近似呈约35°角形成筏状组织,形成的筏状γ′相在三维空间交错生长,γ基体相连续填充在筏形γ′相之间。
     在1040℃/137MPa条件下,[001]、[111]和[011]取向单晶合金的蠕变寿命依次降低;根据不同条件蠕变性能的比较,确定出在高、中温蠕变条件下,[001]取向合金具有较好的蠕变抗力和较长的蠕变寿命,而[011]取向合金的蠕变性能较差。在实验的温度和应力范围内,测定出不同取向单晶合金的表观蠕变激活能分别为Q[001] = 469.56kJ/mol、Q[011] = 396.54kJ/mol和Q[111] = 411.12kJ/mol;应力指数分别为n[001] = 4.77、n[011] = 4.10和n[111] = 5.56。
     [001]取向单晶合金在稳态蠕变期间的变形机制是位错攀移越过筏状γ′相,[001]和[011]取向单晶合金在蠕变后期的变形机制是<110>超位错剪切筏状γ′相;而[111]取向单晶合金在蠕变期间,应变量较大,有较多位错切入筏状γ′相,使其相邻γ′相之间产生取向差,并形成亚晶结构。在蠕变后期,[011]、[111]取向单晶合金首先在筏形γ′/γ两相界面之间出现裂纹,并沿垂直于应力轴方向逐渐扩展,是其合金在高温蠕变期间的主要断裂机制。
In the paper, by means of measurating of creep curves and microstructure observation, an investigation has been made into the microstructure evolution regularity of the single crystal superalloy with different orientations during creep, and the influence of the crystal orientations on the creep behaviors of the single crystal nickel base superalloy.
     Results show that the regular“+”dendritic morphology is displayed in the cross-section of single crystal nickel base superalloy with [001] orientation, and the longer and shorter dendritic are displayed in the cross-section of [011]orientation alloy along the vertical and horizontal directions, and the asymmetry distribution of the dendritic directions along the 60o and 120o angles arrangment is displayed in the cross-section of [111] orientation alloy. After fully heat treated, the microstructure of the superalloys with [001], [011] and [111] orientations consists of that the cubicγ′phase is regularly arranged along the <100> directions, thereinto, the cubicγ′phase in the [011] orientation superalloy is arranged along the direction of 45o angle on (100) crystal plane, and the strip-like raftedγ′phase is formed along [001] orientation during creep. and theγmatrix phase is continuously filled between the raftedγ′phase. The cubicγ′phase in the superalloy with [111] orientation is arranged along the direction of 53o angle on (1?21) plane. During tensile creep, the meah-like raftedγ′phase is formed [111] orientation alloy along the direction of 35o angle on the (?101) plane.
     The creep lifetimes of the superalloy with [001], [111] and [011] orientations reduce in turn, under the condition of 1040℃/137MPa. Compared to the [011] and [111] orientations alloys, [001] orientation alloy displays a better creep resistance and longer creep lifetime under the conditions of high and intermediate temperatures. In the range of the experimental temperatures and stresses, the strain rates of the superalloys with [001], [011] and [111] orientations during steaty state creep obey to Dorn rate equation. In the further, the activation energies of the superalloys with [001]、[011] and [111] orientations are calculated to be Q[001] = 469.56kJ/mol, Q[011] = 396.54 kJ/mol and Q[111] = 411.12kJ/mol respectively, and the stress exponents are calculated to be n[001] =4.77、n[011] =4.10 and n[111] =5.56 respectively. The dislocation climbing over theγ′raft phase is thought to be the deformed mechanism of the alloy with [001] orientation during the steady state creep. In the later stage of creep, the deformed mechanism of the alloys with [001] and [011] orientations is <110> super-dislocation shearing into the raftedγ′phase. Significant amount of dislocations appear in the [111] orientation alloy during creep due to the bigger strain, which result in the form of the subgrain as creep goes on.
     In the later stage of creep, the microcracks are initiated in the interfaces of the raftedγ′/γphase in the [011] and [111] orientations supperalloy, and propagated on the interfaces of the raftedγ′/γphase along the direction vertical to the applied stress axis as creep goes on, which is thought to be the fracture mechanism of the alloys during creep.
引文
[1]郑运荣,张德堂.高温合金与钢的彩色金相研究,北京,国防工业出版社, 1999: 1-5.
    [2] White R A, Lau Y. Method of repairing directionally solidified and single crystal alloy parts. Metals Handbook, 10th edition, Vol. 1, Properties and Selection. 1990: 981-1006.
    [3]吴昌新,孙传棋,李其娟.γ′粒子尺寸对定向凝固高温合金拉伸和持久性能.航空材料学报, 2002, 22(3):1-4.
    [4] Mclean M. Directionally solidified materials for high temperature service. London. Superalloys 1983, Warrendale: TMS, 1983: 9-14.
    [5]张祖谦,刘志中.涡轮叶片用高温合金发展中的几个问题.国际航空, 1978 (4): 43-48.
    [6]师昌绪.中国高温合金四十年.北京:中国科学技术出版社,1996: 1-8.
    [7]汤鑫,刘发信,韩梅.高温合金细晶铸造技术研究.材料工程, 1997 (9): 24-25.
    [8] Giamei A F, Anton D L. Effect of Rhenium additions on microstructure of a Ni-base superalloy. Metal mater trans, 1985, 16A: 1997-2005.
    [9]陈荣章.单晶高温合金发展现状.材料工程, 1995 (9): 3-12.
    [10]何明辉,李海燕,聂景旭. DD6单晶合金的高温蠕变损伤研究.燃气涡轮试验与研究, 2002 15(2): 24-28.
    [11] Versnyder F L, Guard R W. Directional grain structures for high temperature strength. Scripta Metall Mater, 1960 (52): 485-493.
    [12] Gell M, Dupta D N, Sheffler K D. High temperature super conductors with Tc over 30K. Journal of Metals, 1987 (7): 11-15.
    [13]田素贵.单晶镍基合金组织演化与蠕变行为及微观特征的研究:[博士学位论文].沈阳:东北大学, 1998.
    [14]陈金国.军用航空发动机的发展趋势.航空科学技术, 1994 (5): 9-12.
    [15]陈荣章.北京航空材料研究院铸造高温合金发展40年.材料工程, 1998 (10): 3-7.
    [16] Cetel A D, Duhl D N. Second-generation nickel-base single crystal superalloy. Symp on Superalloys 1988, Proc. 6th Int.: TMS, 1998: 2-12.
    [17] Blavette D, Caron P, Khan T. An atom-probe study of some fine-scale microstructural features in Ni-based single crystal superalloys. Superalloys 1988, Reichman S, et al. eds. The Metallurgical Society, 1988: 3-12.
    [18] Erickson G L. The development and application of CMSX-10, Superalloys 1996, Kissinger R D, Deye D J, Cetel A D, et al. eds. TMS, 1996: 35-47.
    [19] Erickson G L. The development of the CMSX -11B and CMSX -1lC alloys for industrial gas turbine application. Superalloys 1996, Kissinger R D. eds. TMS, 1996: 45-53.
    [20] Walston W S and Rose E W. ReneN6. Third generation single crystal superalloy. Superalloys 1996, Kissinger R D, Deye D J, Cetel A D, et al. eds. TMS, 1996: 27-39.
    [21]陈荣章,王罗宝,李建华.铸造高温合金发展的回顾与展望.航空材料学报, 2000, 20(1): 55-61.
    [22]孔祥鑫.第四代战斗机及其动力装置.航空科学技术, 1994 (5): 21-27.
    [23]石琳.涡轮叶片用单晶高温合金的发展.航空工程与维修, 2000 (6):35-36.
    [24] Walston S, Cetel A, MacKay R. Joint development of a fourth generation single crystal superalloy. Superalloys 2004, The Minerals, Metals & Materials Society: TMS, 2004: 15-24.
    [25] Burgel R, Grossmann J. Development of a new alloy for directional solidification of large industrial gas turbine blades. Superalloys 2004: 25-34.
    [26] Rickson G L. Proc of second pacific rim international conference on advanced materials and processing (PRCIM-2). Kyongju, Korea, 1995 : 18-24.
    [27] Walston W S, Ross, E W, Pollock, Y M, et al. Nickel-base superalloy and article with high temperature strength and improved stability, USP 5455120, 1993: 12-14.
    [28] Didier A, Cyril V, Yves D, et al. Dominique. MC-NG: A 4th generation single-crystal superalloy for future aero-nautical turbine blades and vanes, Superalloys 2000, Pol-lock T M, Kissinger R D, Bowman R R, et al. eds. TMS, 2000 : 829-832.
    [29]魏朋义,杨治国,程晓鸣等. DD3单晶高温合金拉伸蠕变各向异性.航空工业学报, 1999, 19(3): 7-12.
    [30]金涛,孙晓峰,赵乃仁等.单晶镍基高温合金DD8激光快速熔凝组织.金属学报, 2009, 45(6) : 711-716.
    [31]刘金来,金涛,张静华等.晶体取向对镍基单晶高温合金铸态组织和偏析的影响.中国有色金属学报, 2002, 12(4):764-768.
    [32]沙玉辉,张静华,徐永波等.镍基单晶高温合金定向粗化行为的取向依赖性.金属学报, 2000, 36(3) : 254-261.
    [33]彭志远,任遥遥,樊宝珍等.镍基单晶高温合金γ′的定向粗化机理.金属学报, 1999, 35(1): 9-14.
    [34]崔传勇,郭建亭,齐义辉等.定向凝固NiAl-28Cr-5.8Mo-0.2Hf合金的高温拉伸蠕变行为.金属学报, 2002, 10(3): 342-346.
    [35]郭建亭.一种性能优异的低成本定向凝固镍基高温合金DZ417G.金属学报, 2002, 38(11): 1163-1174.
    [36] Caron P, Ohta Y, Nakagawa Y G, et al. Creep deformation anisotropy in single crystal superalloys. Superalloys 1988, The Metallurgical Society: TMS, 1998: 15-22.
    [37] Sass V, Glatzel U, Feller-kniepemier M. Anisotropic creep properties of the nickel-based superalloys CMSX4. Acta Mater, 1996, 44(5): 1967-1972.
    [38] Erickson G L. Third generation SX casting superalloy. Paper Presented at the Second Pacific Rim International Conference on Advanced Materials and Processing (PRICM-2), Kyongju, Korea, 1995, (6):18-22.
    [39] Courbon J, Ignat M, Louchet F. Compression creep of <110>- oriented single crystals of nickel-base superalloy CMSX-2. Acta Metall. Mater., 1990, 38(4): 118-124.
    [40] Rebecca, Mackay A. The influence of orientation on the stress rupture properties of nickel-base superalloy single crystals. Metall. Trans., 1982, 13(10): 1747-1754.
    [41] Kear B H, Piearce B J. Tensile and creep properties of single crystals of the nickel-base superalloy Mar-M200. Trans. TMS-AIME, 1967, (239): 1209-1215.
    [42]彭志方, Glatzel U, Feller-Kniepmeier M.一种镍基单晶高温合金中γ′沉淀相的定向粗化.金属学报, 1995, 31(12): 371-375.
    [43] Tien J. K, Copley S. M. The effect of uniaxial stress on the periodic morphology of coherent gamma prime precipitates in nickel-base superalloys crystals. Metall. Trans., 1971, 2(1): 215-219.
    [44] Pollock T M, Argon A S. Directional coarsening in Nickel-base single crystals with high volome fractions of coherent precipitates. Acta Metall. Mater., 1994, 42(2): 1859-1872.
    [45]彭志方,任遥遥,樊宝珍等.镍基单晶高温合金CMSX-2持久拉伸的显微组织形态及力学行为.金属学报, 1999, 35(3): 265-270.
    [46]田素贵,张静华,杨洪才等.一种单晶镍基合金蠕变期间γ′相的定向粗化机制.金属学报, 1998, 18 (3): 16-21.
    [47] Caron P, Khan T. Improvement of creep strength in a nickel based single crystal superalloy by heat treatment. Mater. Sci. Eng., 1983, (61): 173-184.
    [48] Francois L. Directional coarsening of nickel based superalloys driving force and kinetics. Superalloys 1996, Edited by R.D.Kissinger, D.J.Deye, D.L.Anton and A.Woodford, TMS, 1996 : 181-190.
    [49] Fahrmann E, Pollock T M. An experimental study of the role of plasticity in the rafting kinetics. Superalloys 1996, Edited by R.D.Kissinger, D.J.Deye, D.L.Anton and A.Woodford, TMS, 1996 : 191-199.
    [50] Veron M, Brechet Y, Louchet F. Strain induced directional coarsening in Ni-based superalloys. Scripta Metall., 1996, (34): 1883-1892.
    [51] Pollock T M, Argon A S. An experimental study of the role of plasticity in the rafting kinetics of a single crystal Ni-base superalloy. Superalloys 1996, Warrendale, PA: TMS, 1996: 191-199.
    [52] Pearson D D. Lemkey F D, Kear B H. Stress coarsening ofγ′phase and its influence on creep properties of a single crystal superalloy. On Superalloys, Am. Soc. Metals, Metals Park, Ohio, 1980 : 513-519.
    [53] Kondo Y, Kitazaki N, Namekata J, et al. Effect of morphology ofγ′phase on creep resistance of a single crystal nickel based superalloy CMSX-4. Superalloys 1996, Edited by Kissinger R D, Deye D J, Anton D L and Woodford A, TMS, 1996 : 297-304.
    [54] Miura N, Kondo Y, Ohi N. Influence of dislocation substructure on creep rate during accelerating creep stage of single crystal nickel-based superalloy CMSX-4. Superalloys 2000, Edited by Pollock T M, Kissinger R D. TMS, 2000: 377-385.
    [55] MacKay R A, Ebert L J. The development ofγ?γ′lamellar structures in a nickel-base superalloy during elevated temperature mechanical testing . Metall.Trans., 1985, A16(11): 1969-1982.
    [56]孔祥鑫,徐可君.航空发动机叶片的腐蚀与防护.航空科学技术, 1994 (5): 24-26.
    [57]唐定中,李嘉荣,吴仲棠等.低成本的第二代单晶高温合金DD398.材料工程, 1999 (3): 8-10.
    [58] Ha K F. Micro-theory of metal mechanical properties. Beijing: Science press, 1983: 520-525.
    [59] Tian S G, Zhou H H, Zhang J H, et al. Directional coarsening ofγ′phase in single crystalnickel based superalloys during tensile creep. Mater. Sci. Tech., 2000, Vol.16(4), 451-456.
    [60] Yu X F, Tian S G, Du H Q, et al. Microstructure evolution of a pre-compression nickel-base single crystal superalloy during tensile creep. Mater. Sci. Eng., 2009, 506(1): 80-86.
    [61] Eshelby J D. The determination of the elastic field of an ellipsoidal inclusion and related problems. Proceedings of the Royal Society, London, 1957, A241:376-396.
    [62] Eshelby J D. Elastic inclusions and inhomogneities. Prog Solid Mech, 1961 (2): 87-91.
    [63]郭喜平,傅恒志,孙家华.单晶高温合金中γ′筏形组织的形成及转动.金属学报, 1994, 30(7): 321-326.

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700