在α - ω Zr混合物中的张应力-塑性应变场,转换动力学和钻石细胞中的摩擦
Valery I Levitas1,2,3, Achyut Dhar4, K K Pandey5
1Department of Aerospace Engineering, Iowa State University, Ames, IA, 50011, USA. vlevitas@iastate.edu.
Nature communications
|September 23, 2023
概括
这项研究引入了一种新方法,用于测量在中高压相变的应力和塑料应变. 这一进步使定量高压科学成为可能,影响从材料合成到地球物理学的领域.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 高压科学科学 高压科学
背景情况:
- 高压现象如相位转换受应力和塑性应变张器的影响.
- 在钻石细胞中直接测量这些张量器一直是一个重大挑战.
研究的目的:
- 开发和验证结合实验-分析-计算方法,用于测量应力和塑料应变场.
- 在高压和塑性变形下研究的α-omega相转换.
主要方法:
- 利用同步射线X射线衍射来解决一个反向问题.
- 在相转换之前,期间和之后分析应力和塑料应变张器.
- 采用结合的实验-分析-计算策略.
主要成果:
- 成功确定了应力和塑料拉伸张力和摩擦规则的所有组件.
- 确定Zr中应变诱导的α-omega相转换的最小压力为2.7 GPa.
- 证明了这种转换压力与先前的塑料应变和压缩剪切路径的独立性.
结论:
- 开发的方法提供了对高压/压力科学的定量见解.
- 验证和量化了一个理论上预测的塑料应变控制的动力方程.
- 开辟了机械化学,材料合成,地球物理学,天文地质学和部落学的新途径.
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