不同氮含量焊丝熔化极气体保护焊高氮钢的微观组织与力学性能  

Microstructure and Mechanical Property of High-nitrogen Steel with GMAW Welding Wires with Different Nitrogen Contents

作　　者：马良超 王大锋 马冰[1] 陈东高[1] 张迎迎[1] MA Liangchao;WANG Dafeng;MA Bing;CHEN Donggao;ZHANG Yingying(Welding Technology Department, Ningbo Branch of Chinese Academy of Ordnance Science, Ningbo 31503, Zhejiang, China)

机构地区：[1]中国兵器科学研究院宁波分院焊接技术专业室,浙江宁波315103

出　　处：《兵工学报》2021年第6期1303-1311,共9页Acta Armamentarii

基　　金：国防基础科研项目(JCKY2016208A001)。

摘　　要：为研究不同氮含量焊丝对高氮钢焊缝组织性能的影响,采用自制的0.46[N]、0.61[N]、0.84[N]3种不同氮含量焊丝进行高氮钢熔化极气体保护焊焊接工艺试验。测试分析3种成分焊丝焊缝的固氮效果、气孔倾向、微观组织及力学性能。结果表明:随着焊丝氮含量的增加,焊缝氮含量升高,气孔倾向也增大;3种焊丝焊缝组织均由奥氏体+铁素体组成,焊缝组织形态主要取决于焊缝的凝固模式,由焊缝中的各种合金元素共同作用决定;焊缝力学性能主要受铁素体含量及其分布的影响,铁素体含量越高且呈沿晶分布,焊缝硬度、强度越高,韧性越差;当焊缝凝固模式为奥氏体凝固模式、奥氏体-铁素体凝固模式时,焊缝氮含量越高,焊缝拉伸性能越好;气孔缺陷主要影响焊缝的冲击韧性,气孔增多,焊缝冲击韧性下降。In order to study the structures and properties of high-nitrogen steel welds with different nitrogen content welding wires,three kinds of welding wires with different nitrogen contents of 0.46[N],0.61[N]and 0.84[N]were used in gas metal arc welding(GMAW)tests of high-nitrogen steel,and the nitrogen fixation effect,porosity,microstructure and mechanical properties of the welds were tested and analyzed.The results show that,as the nitrogen content of welding wire increases,the nitrogen content of weld increases,and the porosity tendency increases;the microstructures of three welding wires are composed of austenite and ferrite,the microstructure of weld is mainly determined by the solidification mode of weld,which is determined by the joint action of various alloying elements in the weld;and the mechanical properties of welds are mainly affected by the content and distribution of ferrite.The higher the ferrite content and the distribution along the grain are,the higher the hardness and strength of the weld are,and the worse the toughness is.When the weld solidification mode is A or AF,the nitrogen content of the weld is higher,the tensile property of the weld is better.The pore defect mainly affects the impact toughness of the weld,and the increase in pores reduces the impact toughness of the weld.

关 键 词：高氮钢焊丝 熔化极气体保护焊 氮含量 微观组织 力学性能 

分 类 号：TG422.3[金属学及工艺—焊接]