热处理对9Ni钢焊接接头组织和性能的影响  

Effect of Heat Treatment on Microstructure and Properties of 9Ni SteelWelded Joint

作　　者：彭清和[1] 颜文煅 张颜艳[1] 林志灿[1] PENG Qinghe;YAN Wenduan;ZHANG Yanyan;LIN Zhican(College of Photoelectrical and Electromechanical Engineering,Minnan University of Science and Technology,Shishi 362700,Fujian Province)

机构地区：[1]闽南理工学院光电与机电工程学院,福建石狮362700

出　　处：《沈阳工程学院学报（自然科学版）》2024年第2期91-96,共6页Journal of Shenyang Institute of Engineering:Natural Science

基　　金：泉州市“揭榜挂帅”科技重大项目(2022GZ8);福建省自然科学基金面上项目(2021J01530)。

摘　　要：针对运输船用9Ni钢,明晰9Ni钢焊接接头在低温下的塑韧性恶化机理。经手工电弧焊加工后,研究热处理工艺对9Ni钢焊接接头组织和性能的影响规律。结果表明:经调质(QT)热处理后,接头热影响区逆转奥氏体一般分散在晶界周围,马氏体板条界上也有析出的趋势,但和晶界分布相比其含量极少;相比QT热处理,经过两相区(QLT)工艺后接头热影响区的逆转奥氏体数量增加许多,弥散分布在各种晶界处且晶粒更加细小;熔合区的组织更加细小,更加弥散,板条马氏体更明显,方向性更好,主要是L阶段有一定的细化晶粒作用;接头焊缝的冲击吸收能量增加更多,QLT可以让焊缝低温韧性提升更多;两种热处理工艺下冲击断口都为典型的韧窝型断口。The deterioration mechanism of plastic toughness of welded joints of 9Ni steel for cargo shipsat low temperature was clarified.After manual arc welding,the effect of heat treatment on the microstructure and properties of 9Ni steel welded joint was studied.The results show that after QT heat treatment,the reversion austenite in the joint heat affected zone is generally dispersed around the grain boundaries,and there is also a trend of precipitation at the martensitic lath boundaries,but the content is very small compared with the grain boundary distribution.Compared with QT heat treatment,after QLT process,the amount of reversed austenite in the heat affected zone of the joint increases greatly,and the grains are dispersed in various grain boundaries and smaller.The structure of the fusion zone is finer,more dispersed,the lath martensite is more obvious,and the directivity is better.The impact absorption energy of the joint weld increases more,and QLT can improve the low temperature toughness of the weld more.The impact fractures under the two heat treatment processes are typical dimple fractures.

关 键 词：热处理 焊接接头 组织 性能 

分 类 号：TG156[金属学及工艺—热处理] TG406[金属学及工艺—金属学]