摘要
利用热模拟技术,对高氮钢激光焊接热影响区(HAZ)的组织和性能进行了研究。结果表明,高氮钢焊接热影响区组织为奥氏体和δ-铁素体。随着焊接冷却速度的增大,高氮钢粗晶区的显微硬度增大;随着焊接峰值温度降低,热影响区显微硬度逐渐减小。焊接热影响区显微硬度均高于母材,没有出现软化区。随着冷却速度的增大,热影响区粗晶区的冲击吸收功先上升然后降低,而整个热影响区出现了两处脆化区。
The microstructure and mechanical properties of heat-affected zone(HAZ) of high nitrogen steel(HNS) were investigated by using thermo-simulation technique.The experimental results indicate that the microstructure in the HAZ of HNS is austenite and δ-ferrite under laser welding conditions.The hardness of the coarse-grained heat-affected zone(CGHAZ) increases when the cooling rate increases,and the one of the HAZ decreases while the peak temperature decreases. The results show that the hardness of the HAZ is higher than the one of the base metal,indicating no softening of the HAZ under appropriate welding conditions.The impact toughness of CGHAZ is improved with the increase of the cooling rate,whereas two brickle zones exist in the HAZ.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2007年第12期26-30,共5页
Transactions of The China Welding Institution
基金
国家重点基础研究计划(973)项目(2004CB619103)
中国博士后科学基金资助项目(20060390417)
关键词
高氮钢
激光焊接
热影响区
组织
性能
high nitrogen steel
laser welding
heat-affected zone
microstructure
mechanical properties
