研究了单轴预压缩对镍基单晶高温合金DD98的微观组织和持久性能的影响及其原因.在热处理态的基础上, 于真空中1050 ℃下分别实施了180 MPa/6 h和220 MPa/6 h两种预压缩. 观察到预压缩后的试样中形成了与应力轴平行的P型γ'筏. 同时, 在竖直通道内的γ/γ'界面上形成了位错网. 单轴预压缩对持久寿命的影响因测试条件不同而变化, 但预压缩试样的延伸率均得到提高. 在高温低应力持久时, 预压缩形成的P型筏转化为宽度不同的波浪状N型筏, 导致位错越过γ'方式有所差异. 在低温高应力时, P型筏仅表现出微弱的向N型筏转化的趋势. 此时, 两种预压态试样中均形成位错缠结. 在中等温度及应力时, 两种预压态中的P型筏则转化为较混乱的N型筏, 其位错特征是不规则位错网.
The effect of uniaxial pre-compression on the microstructure and stress rupture properties of an second generation single crystal superalloy without Re is studied. The pre-compression is performed in vacuum at 1050℃ by 180MPa/6h and 220MPa/6h respectively. It is shown that P type γ’ paralleling to stress is formed during pre-compression, which is more regular in the 220MPa compressed sample. Moreover, dislocation networks are deposited on γ/γ’ interface in vertical channels, while a few dislocations have cut into γ’ particles in 220MPa compressed sample. The effect on stress rupture lifetime vary with the test conditions, but pre-compression increased the elongations under all test conditions.
参考文献
| [1] | |
| [2] | |
| [3] | |
| [4] | |
| [5] | |
| [6] | |
| [7] | |
| [8] |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%