对充分退火的、晶粒尺寸超过10 mm的99.999％纯Al试样在Schenck试验机上进行了恒应变幅的对称拉-压疲劳试验。应变幅的范围从2.82×10~(-4)到6.1×10~(-3)。测量了各个循环之后的拉、压半周的峰值应力。在所用应变范围内,都观察到二次循环硬化,并在大约3.0×10~(-3)的应变幅处有一个最大值。 金相和电子扫描显微镜的观察表明,在高应变幅下,在晶界区域内产生不同的塑性应变,导致与穿晶裂纹联接的晶界滑动和迁移。在同一断裂面上存在不同型式的疲劳条纹。 作为简单的讨论。假定二次硬化是二次滑移和晶界滑动过程中局部硬化的结果。
Symmetric push-pull fatigue was performed on well annealed 99.999% purity Al specimens with grain sizes up to 10 mm under constant strain amplitude in a Schenck machine. The applied strain amplitudes ranged from ±2.82×10~(-4) to ±6.1×10~(-3). Peak stresses in both tensile and compressive half-cycle after various cycles were measured. A secondary cyclic hardening was observed at all strain amplitudes used. A maximum of the hardening is presented at a strain amplitude of about 3×10~(-3).The metaUograph and SEM observations indicated that at high strain amplitude the various plastic deformations occur in the region of grain boundary which cause the grain boundary glide and migration with intergranular cracking. It was also found that different types of fatigue striations coexist on the same fracture surface.A brief discussion was made of the secondary cyclic hardening which is assumed to result from the local hardening due to the secondary slip and grain boundary sliding.
参考文献
| [1] | |
| [2] | |
| [3] | |
| [4] | |
| [5] | |
| [6] | |
| [7] | |
| [8] | |
| [9] | |
| [10] | |
| [11] | |
| [12] | |
| [13] | |
| [14] | |
| [15] |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%