摘要
利用CO_2激光对1Cr5Mo耐热钢焊接接头进行表面热处理,通过4XC型光学显微镜对激光热处理前后焊接接头各区显微组织和晶粒度等级进行分析,并采用X射线应力仪测定激光热处理前后焊接接头残余应力和残余奥氏体的分布规律。结果表明:经激光热处理后1Cr5Mo耐热钢焊接接头表面晶粒发生细化,焊缝区、熔合区、过热区和正火区晶粒等级由9级、9.8级、8级和10.7级提升至10级、10.2级、8.5级和11级,组织结构薄弱区域由过热区、焊缝区和熔合区减少为过热区,均匀性得到了明显改善;激光热处理消除了焊接接头表面残余拉应力,形成了深度约为0.28mm的残余压应力层,残余奥氏体含量有所提高,分布更均匀,有利于改善其力学性能。
The surface of 1Cr5Mo heat-resistant steel welded joint was treated with CO2 laser, the mi-crostructure and grain size grades of welded joints before and after laser heat treatment （LHT） were analyzed with 4XC type optical microscope （OM） , and the distribution of residual stress and retained austenite content in the surface of the welded joints were measured with X-ray diffraction （XRD） stress tester. The results show that the grains of 1Cr5Mo steel welded joints are refined by LHT, and the microstructure uniformity improves significantly, the grain levels of welded zone, fusion zone, overheated zone and normalized zone increase from level 9, level 9. 8, level 8 and level 10. 7 to level 10, level 10. 2, level 8. 5 and level 11 respectively, the mechanical weak areas reduce from overheated zone, welded zone and fusion zone to the overheated zone. The tensile residual stress in the welded joint surface is eliminated by LHT and a layer of compressive residual stress with thickness of about 0. 28mm is formed. The residual austenite content in the welded joint surface increases after LHT, of which the distribution is more uniform and conducive to the improvement of mechanical properties.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2017年第1期65-71,共7页
Journal of Materials Engineering
基金
江苏省科协首席专家(工程师)资助项目(2013-216)
江苏省普通高校研究生科研创新计划资助项目(CXLX14-1098)
作者简介
通讯作者：孔德军（1966-）,男,教授,博士,主要从事激光表面改性处理方面的研究工作,联系地址：江苏省常州市常州大学机械工程学院（213164）,E-mail：kong-dejun@163.com
