揭示了变形引起的超和机制
Karoline S Kormout1, Lorenz Romaner2, Daniel Scheiber3
1Erich Schmid Institute of Materials Science, Austrian Academy of Sciences, Leoben, Austria.
Scientific reports
|July 2, 2024
概括
铜银合金的高压扭转导致银沉物溶解到铜矩阵中. 完全溶解发生在银区域缩小到5nm以下时,由热力学原理解释.
科学领域:
- 材料科学 材料科学 材料科学
- 物理金学 物理金学
- 纳米材料是一种纳米材料.
背景情况:
- 了解合金中的沉物溶解对于控制材料特性至关重要.
- 高压扭转 (HPT) 是一种有效的严重塑料变形技术,用于结构改进.
- 铜银 (Cu-Ag) 合金表现出有趣的相位行为和潜在的应用.
研究的目的:
- 为了研究高压扭曲对Cu-6at%Ag合金微观结构的影响.
- 为了确定银沉物在铜矩阵中溶解的临界大小.
- 阐明在严重的塑性变形过程中控制沉物溶解的原子化机制.
主要方法:
- 高压扭转 (HPT) 应用于Cu-6at%Ag合金的各种应变级别.
- 使用先进技术 (例如电子显微镜) 进行微结构性表征.
- 原子学计算 (例如,密度函数理论) 来分析相位稳定性和接口.
主要成果:
- 持续的结构提炼和沉溶解观察到与日益增长的应变.
- 银 (Ag) 沉物在铜 (Cu) 基质中完全溶解需要在5nm以下的区域.
- 原子学计算显示,溶解是由固体溶液和中间层结构之间的度差异驱动的.
结论:
- 通过HPT进行严重的塑性变形有效地提炼了微观结构,并促进了Cu-Ag合金中的沉物溶解.
- 对于Ag沉物来说,确定了大约5nm的临界尺寸值,以实现完全溶解.
- 热力学驱动力,特别是度差异,解释了在纳米尺度上观察到的溶解行为.
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