摘要
采用焊接热模拟、电子显微分析、力学性能测试等技术手段,研究了国产9Ni钢在多种焊接热输入条件下焊接热影响粗晶区的低温韧性,讨论了多次焊接热循环对9Ni钢焊接热影响区组织性能的影响规律,以及不同焊接热过程中的组织特征和脆化倾向。研究结果表明,9Ni钢并不适合采用单道焊,在多道焊接过程中,后续焊道的热作用可以良好地改善其低温韧性,粗大晶粒组织的重结晶是提高低温韧性的主要因素。
The low temperature toughness in coarse-grained（CG） HAZ of 9Ni steel in different heat input was studied through welding thermal simulation technique, TEM, SEM and mechanical properties test. The influences of single-pass thermal cycle and multi-pass thermal cycle on the microstructure and properties were discussed respectively,and the microstructure and embrittlement mechanism were also discussed. The results show that single-pass welding is not fit for 9Ni steel. The low temperature toughness of CGHAZ in the steel is improved effectively by heat treatment of the next welding thermal cycle in multi-pass welding. And the main factor of improving low temperature toughness is the recrystallization of the steel.
出处
《金属热处理》
CAS
CSCD
北大核心
2009年第2期70-74,共5页
Heat Treatment of Metals
基金
中国石油天然气集团长庆石油勘探局科技攻关项目:LNG工程用超低温钢焊接技术研究项目(CQJG2005-技术(开发)-002)
关键词
9NI钢
热模拟
焊接热循环
低温韧性
9 Ni steel
thermal simulation
welding thermal cycle
low temperature toughness
