摘要
对20mm厚10CrNi3MoV钢用机器人进行多层单道熔化极活性气体(Metal Active Gas,MAG)保护焊焊接,采用光学显微镜(Optical Microsope,OM)观察焊接接头组织分布,采用硬度计和疲劳试验机分析焊接接头的硬度和疲劳性能.结果表明:焊接接头热影响区(Heat Affected Zone,HAZ)宽度小,其硬度比母材硬度高,HAZ没有造成焊接接头强度软化.二次热循环作用使得焊缝粗晶区晶粒显著细化,焊缝区维氏硬度(HV)谷值约为170,母材硬度约为250.焊接接头应力在屈服点80%时低周疲劳试验循环10 000次没有断裂,而在屈服点90%时循环3 254次后断裂,并且断裂发生在焊趾处.
The 10CrNi3MoV steel with the thickness of 20 mm was welded by multi-layer single-track robot metal active gas （MAG） welding, microstructures of the weld joint was observed by optical microsope （OM）. The hardness and fatigue properties of the weld joint were respectively analyzed by Vickers hardness and fatigue tester. The results show that the heat affected zone（HAZ） width of the weld joint is small,the hardness is higher than that of the base metal,and the HAZ does not soften the strength of the welded joint. The secondary thermal cycling makes the grains of the coarse grain region of the weld significantly refined. The hardness valley of weld seam is about 170 while the hardness of base metal is about 250. At the yield point of 80% ,the weld joint is not fractured in low cycle fatigue test with cycling 10 000 times,but it is fractured at the yield point of 90~ with the cycling of 3 254 times,and the fracture occurs at the weld toe.
作者
王远
杨尚磊
刘浩博
谢超杰
WANG Yuan YANG Shanglei LIU Haobo XIE Chaojie(School of Materials Engineering, Shanghai University of Engineering Science, Shanghai 201620, China)
出处
《上海工程技术大学学报》
CAS
2017年第2期102-105,135,共5页
Journal of Shanghai University of Engineering Science
基金
上海市汽车工业科技发展基金资助项目(1404)
