新型R407C焊条熔敷金属组织与性能研究
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摘要
国产钢加氢装置用12Cr2Mo1R钢焊条存在主要问题是无法满足-30℃低温冲击韧性和长时间的抗回火脆性要求,长期依赖进口。采用金相显微镜对自主研制的新型R407C焊条熔敷金属显微组织进行观察,应用拉伸、冲击等试验对性能进行测试分析。结果表明:热处理态下的组织为回火贝氏体组织,随着回火参数的增加,晶粒逐渐长大,块状铁素体含量增加,组织逐渐转变为铁素体+碳化物,其强度和韧性逐渐降低;随着焊接热输入增加,焊缝中块状铁素体晶粒增多,其强韧性逐渐降低。
The 12Cr2M1R steel electrode relies on imports for long time. While,the main problem for domestic steel hydrogenation unit is that it can't meet the low temperature impact toughness at-30 ℃ and long-term anti-temper brittleness requirements. The microstructure of the deposited metal of the newly developed R407C electrode was observed by metallographic microscope,and the properties were tested by tensile and impact tests. The results showed that the deposited metal structure of R407C electrode was tempered bainite structure at PWHT. With an increase in tempering parameters,the grain gradually grew up,the bulk ferrite content increased,the structure gradually transformed into ferrite + carbide,and its strength and toughness gradually decreased. As the heat input of welding increased,the massive ferrite grains in the weld increased. And its toughness was gradually reduced.
The 12Cr2M1R steel electrode relies on imports for long time. While,the main problem for domestic steel hydrogenation unit is that it can't meet the low temperature impact toughness at-30 ℃ and long-term anti-temper brittleness requirements. The microstructure of the deposited metal of the newly developed R407C electrode was observed by metallographic microscope,and the properties were tested by tensile and impact tests. The results showed that the deposited metal structure of R407C electrode was tempered bainite structure at PWHT. With an increase in tempering parameters,the grain gradually grew up,the bulk ferrite content increased,the structure gradually transformed into ferrite + carbide,and its strength and toughness gradually decreased. As the heat input of welding increased,the massive ferrite grains in the weld increased. And its toughness was gradually reduced.
引文
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[2]何少卿,张尤红,金光日,等.2.25Cr1Mo耐热钢用R407A焊条的研制[J].焊接技术,1996(5):29-35.
[3]屈岳波,黄欣泉,曹彬,等.残余奥氏体对2.25Cr-1Mo钢焊缝冲击性能的影响[J].机械工程学报,2011,47(14):44-48.
[4]刘正东,张光中,吴光大,等.合金碳化物与21/4Cr-1Mo钢的韧化机制[J].钢铁,1998,33(2):50-53.
[2]何少卿,张尤红,金光日,等.2.25Cr1Mo耐热钢用R407A焊条的研制[J].焊接技术,1996(5):29-35.
[3]屈岳波,黄欣泉,曹彬,等.残余奥氏体对2.25Cr-1Mo钢焊缝冲击性能的影响[J].机械工程学报,2011,47(14):44-48.
[4]刘正东,张光中,吴光大,等.合金碳化物与21/4Cr-1Mo钢的韧化机制[J].钢铁,1998,33(2):50-53.