论文部分内容阅读
应用透射和扫描电镜对镍基高温合金应变疲劳形变结构,损伤过程、裂纹的形成和扩展进行了观察和分析。结果表明:镍基高温合金应变疲劳的形变结构具有平面滑移特性,裂纹沿交叉滑移带形核和扩展。在应变循环下位错仍多以超位错组态运动并切过γ′相。由于反复切割的结果,形成驻留滑移带,通常裂纹在驻留滑移带形核,这就是为什么镍基高温合金具有较低应变疲劳寿命的原因。
Transmission and scanning electron microscopy were used to observe and analyze the strain fatigue deformation structure, the damage process and the formation and propagation of cracks in the nickel-base superalloy. The results show that the strain-induced deformation structure of Ni-base superalloy has plane slip characteristics, and the crack nucleation and propagation along the cross-slip zone. In the strain cycle, there are still many dislocations with super-dislocation configuration movement and cut through the γ ’phase. As a result of repeated cuts, resident slip bands are formed, and the cracks typically reside in slipping band nuclei, which is why nickel-base superalloys have a lower strain fatigue life.