摘要
利用螺旋选晶法制备了一种不含Re的低成本镍基单晶合金,研究合金在不同温度下的蠕变变形机理。结果表明:在850℃×441 MPa条件下,合金的蠕变变形主要是大量位错在基体中的滑移和对增强相的切割;在950℃×250 MPa条件下,合金的蠕变变形主要是位错以层错的形式切割γ′相;在1 040℃×137 MPa条件下,合金的蠕变变形比较复杂,既有位错在基体中的滑移,也有位错攀移通过增强相,同时在γ/γ′界面处形成部分位错网。
A Ni- base superalloy was prepared by screw selecting method and the creep deformation mechanism at different temperatures was investigated. The results show that during creep testing, when the alloy ruptures at 850 ℃ and 441 MPa, the main deformation mechanism is dislocation sliding in γ matrix and the dislocation cutting to γ′. However, when the temperature increases to 950 ℃, the main deformation mechanism is dislocation cutting to γ′ phase by the formation of stacking fault. The deformation mechanism at 1 040 ℃ is more complex, dislocation climbing and cutting were observed, and some dislocation networks form at the interface of γ/γ′.
出处
《兵器材料科学与工程》
CSCD
北大核心
2012年第6期49-52,共4页
Ordnance Material Science and Engineering
关键词
镍基单晶合金
蠕变变形
位错
攀移
层错
Ni-base single crystal superalloy
creep deformation
dislocation
dislocation climbing
stacking fault
