摘要
研究了应变速率对GH4169合金激光焊接接头变形行为的影响,探讨了接头拉伸变形对应变速率敏感性的机理。结果表明,与母材相比,GH4169合金激光焊接接头的拉伸变形对应变速率敏感性的影响更显著。应变速率低于10-1s-1时,接头强度受应变速率的影响不大;当应变速率高于100s-1时,随着应变速率增加接头屈服强度、抗拉强度均呈增加趋势,屈服强度增加的幅度更为显著。随着应变速率增加接头塑性总体呈下降的趋势,但是在101~102s-1范围内有所回升,并出现峰值。随着应变速率的增加,合金接头断裂的位置由母材经过热影响区向熔合区靠近。高应变速率的接头不同位置变形行为对应变速率敏感性的差异,是接头变形和断裂行为产生应变速率敏感性的主要原因。
The effect of strain rate on the deformational behavior of laser welded joint of superalloy GH4169 was investigated, and the mechanism for strain rate sensitivity of the tensile deformation was discussed. The results show that the welded joints were more sensitive to the strain rate compared to the base material. The strain rate had little influence on the strength of welded joints at the strain rate range from 10^-3 s^-1 to 10^-1 s^-1. When the strain rate was higher than 10^0 s^-1, the yield strength and ultimate tensile strength of the welded joint increased with increasing strain rate, at the same time the yield strength had a much obvious increase. On the other hand, the plasticity of the welded joint tended to decrease with the increasing strain rate, however it increased while the strain rate changed from 10^1 s^-1 to 10^2 s^-1 and then reached the peak value of ductility by the strain rate of 10^2 s^-1. The tensile failure location changed from the base material via the softened heat-affected zone to near the fusion zone with the increase of the strain rate. The strain rate sensitivity of deformation and fracture behavior of the welded joint under high strain rate was mainly caused by the difference of strain rate sensitivity of microstructures at differ- ent positions in the welded joint.
作者
赵强
刘杨
王磊
李妨
ZHAO Qiang LIU Yang WANG Lei LI Fang(Key Lab for Anisotropy and Texture of Materials, Northeastern University, Shenyang 110819, China)
出处
《材料研究学报》
EI
CAS
CSCD
北大核心
2016年第12期881-887,共7页
Chinese Journal of Materials Research
基金
国家自然科学基金项目51571052
51371044
中央高校基本科研业务费专项基金项目L1502027
辽宁省自然科学基金项目2014020034资助~~
关键词
金属材料
GH4169合金
激光焊接
应变速率敏感性
变形行为
微观组织演变
metallic materials, GH4169 superalloy, laser welding, strain rate sensitivity, deformationbehavior, microstructure evolution
