焊后热处理对可膨胀管用低Cr合金钢焊缝金属组织性能的影响  

Effect of Post-weld Heat Treatment on Microstructure and Properties of Weld Metal of Low Cr Alloy Steel for Expandable Tube

作　　者：朱霞[1,2] 董俊慧[2] ZHU Xia;DONG Junhui(Metallurgical&Material Engineering Department,Inner Mongolia Technical College of Mechanics and Electrics,Hohhot 010070,China;School of Materials Science and Engineering,Inner Mongolia University of Technology,Hohhot 010051,China)

机构地区：[1]内蒙古机电职业技术学院冶金与材料工程系,内蒙古呼和浩特010070 [2]内蒙古工业大学材料科学与工程学院,内蒙古呼和浩特010051

出　　处：《热加工工艺》2019年第23期177-179,共3页Hot Working Technology

基　　金：内蒙古教育厅自然科学项目(NJZY18273);内蒙古机电职业技术学院院级科研项目(NJDZJ1404)

摘　　要：通过显微组织观察、拉伸性能测试、硬度测试、冲击韧性测试等方法,对不同温度热处理后低Cr合金钢焊缝金属的显微组织和力学性能进行对比研究。结果表明:在740~900℃温度区间内,不同温度焊后热处理的低Cr合金钢焊缝金属组织为铁素体+条状马氏体,随着温度的升高,铁素体逐渐细化。与焊态相比,低Cr合金钢试样经热处理后,焊缝金属强度和硬度均有所下降,焊接金属强度随着热处理温度的升高逐渐降低。740、900℃热处理对低Cr合金钢焊缝金属低温冲击韧性提高不明显,820℃热处理焊缝金属冲击韧性提高显著,-40℃冲击吸收功比焊态提高了27%。The microstructure and mechanical properties of weld metal of low Cr alloy steel after heat treatment at different temperatures were compared by means of microstructure observation,tensile property test,hardness test and impact toughness test.The results show that the microstructure of weld metal of low Cr alloy steel after different temperature post-weld heat treatments in the temperature range of 740-900℃are ferrite+strip martensite.With the increases of temperature,the ferrite becomes finer gradually.Compare with the welded state,the strength and hardness of the weld metal of the low Cr alloy steel samples decrease after post-heat treatment.With the increases of heat treatment temperature,the strength of weld metal decreases gradually.After heat treatment at 740℃,900℃,the increase of low temperature impact toughness of weld metal of low Cr alloy steel is not obvious,the impact toughness of weld metal after heat treatment at 820℃increases significantly and the impact absorbing energy at-40℃is 27%higher than that in welding state.

关 键 词：低Cr合金钢 焊缝金属 焊后热处理 显微组织 力学性能 

分 类 号：TG441.8[金属学及工艺—焊接]