描述稳定状态爬行速率与不断变化的应力灵敏度参数和应用应力的上限
1Dept. of Mathematics and Physics, Military Technology Faculty, University of Defence, Kounicova 65, CZ-662 10, Brno, Czech Republic.
Heliyon
|January 13, 2025
概括
这项研究引入了稳定状态爬行速率的新方程式,通过考虑压力依赖的激活能量和温度诱导的机制变化来改善预测. 这增强了对应力和温度变化下的材料行为的理解.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 固体力学 固体力学是什么
背景情况:
- 平稳状态的爬行速率通常是使用阿雷尼乌斯和功率定律来建模的.
- 目前的模型假设恒定的激活能量和固定的应力灵敏度参数.
- 现有的模型与广泛的温度范围和应力变化作斗争.
研究的目的:
- 为了开发一个更准确的平衡状态爬行速率方程.
- 为了整合压力依赖的激活能量和温度变量的变形机制.
- 为了更好地适应实验性爬行数据.
主要方法:
- 导出了一个新的平衡状态爬行率的方程.
- 考虑了激活能量的依赖于施加的应力.
- 考虑了变形微机理的变化与温度变化.
- 使用实验式爬行测量验证了新的方程.
主要成果:
- 新方程式准确地描述了在更广泛的温度和应力范围内稳定状态的爬行速率.
- 发现激活能量显著依赖于施加的应力.
- 观察到变形机制随着温度的变化而变化.
- 导出方程消除了对 sinh(x) 函数的需求,以建模应力爬行速率曲线.
结论:
- 新的爬行速率方程提供了更好的准确性和更广泛的适用性.
- 了解激活能量的应力和温度依赖性对于准确的爬行模型至关重要.
- 这些发现为预测复杂负载条件下的材料性能提供了更强大的框架.
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