| 摘要: |
| 用陶瓷丸CZ50对DD6单晶高温合金（简称DD6单晶）进行喷丸，研究喷丸后DD6单晶的表面形貌和650 ℃旋转弯曲疲劳应力寿命曲线的变化。结果表明：喷丸消除了加工刀痕，缓和了表面应力集中；DD6单晶喷丸后疲劳极限达到486 MPa，比未喷丸的原始试样提高了19.7%。喷丸后试样疲劳源呈现小刻面状的原因是由于喷丸强化层内较大的位错密度，裂纹扩展方向在距疲劳源30～50 μm处出现变化，延长了单晶高温合金的扩展寿命。 |
| 关键词: 喷丸 DD6单晶高温合金 应力集中 疲劳极限 扩展方向变化 |
| DOI： |
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| Influence of Shot-peening on the High-temperature Fatigue Property of DD6 Single Crystal Superalloy |
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WANG Xin, YOU Hong-de, ZHAO Jin-qian, YANG Qing, TANG Zhi-hui1,2,3
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1. Beijing Institute of Aeronautical Material, Beijing 100095;2. Shenyang Aero-engine Design and Research Institute, Shenyang 110015;3. Shenyang Liming Aero-Engine (Group) Corporation Ltd., Shenyang 110043
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| Abstract: |
| DD6 single-crystal superalloy was used to investigate the effect of ceramic-shot peening (CSP) on surface topography and high-temperature fatigue property. Results show that the tool-marks are removed by CSP, which mitigates the surface stress concentration, and the fatigue limit at 650 ℃ reaches 486 MPa after CSP, which increases by 19% compared with the original. However, a small platform is observed on the distance of 30-50 μm from the fatigue source, which means the change of the propagation direction takes place due to the high dislocation density induced by CSP, which makes the fatiguecrack propagation life prolong. |
| Key words: shot-peening DD6 single-crystal superalloy stress concentration fatigue limit change of propagation direction |
