|
| 预冷变形对Cu-Ni-Si铜合金疲劳性能和破坏行为影响研究 |
| On the effect of precooling deformation on fatigue performance and failure behavior of Cu-Ni-Si alloy |
| Received:August 10, 2017 Revised:September 10, 2017 |
| DOI：10.7520/1001-4888-17-163 |
| 中文关键词: Cu-Ni-Si铜合金 预冷变形 疲劳性能 破坏特性 |
| 英文关键词:Cu-Ni-Si alloy pre-cold working fatigue properties fracture behaviours |
| 基金项目:国家自然科学基金(U1534209)资助 |
| Author Name | Affiliation | | WANG Hua-qiang | State-Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu 610031, China | | WU Ming-ze | State-Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu 610031, China | | ZHANG Ji-wang* | State-Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu 610031, China | | LU Liantao | State-Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu 610031, China |
|
| Hits: 749 |
| Download times: 282 |
| 中文摘要: |
| 为了研究预冷变形处理对Cu-Ni-Si铜合金的疲劳性能和破坏行为的影响，对含有预冷变形处理和不含预冷变形处理的Cu-Ni-Si铜合金进行拉伸实验、疲劳实验、裂纹扩展实验等相关实验，并通过扫描电镜对试样疲劳断口进行观察。结果表明，预冷变形处理大幅提高了材料机械强度、降低了材料韧性，同时使疲劳强度降低，其中，107寿命对应疲劳强度下降4.7%。试样的疲劳破坏均萌生自表面的晶体滑移，预冷变形处理的试样在裂纹扩展阶段表现为穿晶破坏，而不含预冷变形处理的试样在裂纹扩展阶段表现为沿晶和穿晶的混合破坏模式。预冷变形处理试样在裂纹稳定扩展阶段，表现为剪切型破坏，而不含预冷变形处理的试样在裂纹萌生后，裂纹转向在最大拉应力面内扩展直到最终的破坏。由上述结果可知，预冷变形改变了Cu-Ni-Si铜合金的疲劳破坏行为，从而影响了其疲劳性能。 |
| 英文摘要: |
| In order to investigative the effect of precooling deformation treatment on fatigue performance and failure behavior of Cu-Ni-Si alloy, a series of related experiments, such as tensile, fatigue and crack propagation experiment were carried out were carried out for Cu-Ni-Si alloy after precooling deformation treatment and without precooling deformation treatment, respectively. The fatigue fracture of specimen was observed by scanning electron microscope (SEM). Results show that the mechanical strength of material greatly increases and the toughness and fatigue strength decrease due to precooling deformation treatment. Thereinto, the fatigue strength decreases by 4.7% corresponding to the fatigue life of 107. The fatigue failure of all specimens initiate from the crystal slip on the surface. In the crack propagation stage stage, the pre-cold worked specimens show transgranular fracture, while the no pre-cold worked specimens show mixed fracture mode consisted of both transgranular and intergranular. The pre-cold worked specimens in the crack propagation stage show as shear failure mode, but the cracks in pre-cold worked specimens propagate under the maximum tensile stress until the final failure. It can be found that the pre-cold worked treatment changes the fatigue fracture behavours of the material, so it changes the fatigue property. |
| View Full Text Download reader |
| Close |
