与约束相关的微观疲劳裂传播行为多晶合金的多晶合金
1Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering, School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, PR China.
Heliyon
|February 6, 2024
概括
在GH4169合金中的微观多晶疲劳裂传播 (MPFCP) 对微限和初始裂角度敏感. 更高的约束导致更直的裂路径和更快的传播速度.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 金工业是金工业的一个方面.
背景情况:
- 疲劳裂传播是金属合金中关键的故障机制.
- 了解微观多晶疲劳裂纹传播 (MPFCP) 对于预测材料寿命至关重要.
- GH4169合金广泛用于高温应用,需要详细的疲劳分析.
研究的目的:
- 为了研究GH4169合金在不同微限条件下的MPFCP行为.
- 分析初始裂纹角度对MPFCP特征的影响.
- 阐明应力分布,裂路径和传播速率之间的关系.
主要方法:
- 使用了一种微观的多晶疲劳裂传播 (MPFCP) 模型.
- 在不同的微孔深度和长度 (约束) 下模拟MPFCP.
- 探索了初始裂角度对裂传播动态的影响.
主要成果:
- 由于谷物边界,谷物大小和应力状态的差异,MPFCP路径随着微限的约束而显著变化.
- 更高的约束导致了更直的MPFCP路径.
- MPFCP速率与微口大小和加载方向相关,在较低的约束条件下需要更多的应力积累.
- 最初的裂角度主要影响了谷物内部的MPFCP路径,并对传播速率产生了更大的影响.
结论:
- 微限和初始裂纹角度是GH4169合金中MPFCP的关键因素.
- 这项研究提供了关于在复杂的压力条件下疲劳裂生长的微观机制的见解.
- 这些发现可以为由GH4169合金制成的组件的设计和寿命预测提供信息.
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