摘要
通过扫描电镜原位拉伸实验,动态跟踪观察了2种非金属夹杂物对FGH95合金裂纹萌生和扩展的影响规律。结果表明,裂纹在夹杂物处萌生,塑性莫来石类夹杂的尖角处,是裂纹萌生的择优位置。在最大正应力和最大剪应力的作用下,裂纹沿与主应力轴垂直或约45°向夹杂内部扩展。当裂纹扩展到基体中之后,呈锯齿状向基体内扩展,但主裂纹所在平面仍与主应力轴垂直,其尖端变形带内有明显的滑移线出现。夹杂物附近基体中的贫γ′相区,断口呈韧性沿晶断裂,而远离夹杂物的基体处则变为穿晶断裂。
Two kinds of non-metallic inclusions with different effects on fracture initiation and propagation in FGH95 superalloy were investigated by SEM in-situ tension experiment. The results show that the fractures were initiated from inclusion, especially, mullite comer, and then propagated into inclusion vertically or about 45° with stress axis. After propagating into the matrix, the fracture went along the vertical plane with obvious slipping around it. The specimen was ruptured along crystal surfaces in the matrix of poor in γ′ phases near the inclusion, but broken through the crystals in the matrix far from the inclusion.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2007年第2期231-235,共5页
Rare Metal Materials and Engineering
