激光熔化沉积Ti-6Al-2Zr-Mo-V合金

Deformation Behavior in High-Frequency Fatigue Failure of Laser Melting Deposited

摘要:

研究激光熔化沉积Ti-6Al-2Zr-Mo-V合金在高周疲劳失效中的变形行为，并提出相应的变形机制。结果表明，激光沉积钛合金疲劳裂纹萌生和扩展中的变形行为都与其位错运动和滑移行为密切相关。疲劳裂纹扩展中的滑移主要沿两个滑移面进行；裂纹扩展亚表面存在大量二次裂纹。解释两种不同类型二次裂纹的形成机制和作用。分析粗大柱状晶晶界变形特征

Abstract:

Deformation behavior in high-frequency fatigue failure of laser melting deposited Ti-6Al-2Zr-Mo-V alloys was investigated. The deformation modes and mechanisms were also discussed. The results indicate that the deformation behavior during fatigue crack nucleation and propagation are closely related to the dislocation motion and slip behavior. The fatigue cracks by slip deformation propagate along two slip planes. A lot of secondary cracks were observed on the crack propagation subsurface. Formation mechanism and effect of two types of secondary cracks were explained. Grain boundary deformation of coarse-columnar crystal was also discussed.