在一个有序的高合金中,压力诱导不可逆转的相变
Andrew D Pope1, Bijun Xie2, Raimundas Sereika1
1Department of Physics, University of Alabama at Birmingham, Birmingham, AL, 35294, USA.
Scientific reports
|July 2, 2025
概括
高压实验揭示了有序高合金 (EHEAs) 中不可逆转的相变. B2阶段促进了B2到FCC的快速转化,发生的压力明显低于之前观察到的压力.
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
- 金工业是金工业的一个方面.
背景情况:
- 订序的高合金 (EHEAs) 在外部刺激下表现出独特的相位行为.
- 了解压力诱导的转变对于设计先进材料至关重要.
研究的目的:
- 为了研究压力诱导的相位转换在一个有序的Eutectic高合金 (EHEA) AlCoCrFeNi2.1.
- 确定相变的临界压力,并与其他EHEA处理方法进行比较.
主要方法:
- 使用弧形融合成AlCoCrFeNi2.1EHEA的合成.
- 在高压X射线衍射 (XRD) 中,钻石细胞的压力高达73 GPa.
- 传输电子显微镜 (TEM) 用于微观结构分析.
- 分子动力学模拟以支持实验发现.
主要成果:
- 吸EHEA样本由有序的B2相 (Ni,Al-rich) 和无序的FCC相 (Fe,Cr,Co-rich) 组成.
- 观察到一个不可逆转的B2到FCC相位转换,完成3GPa.
- 这种转换压力远低于添加制造的EHEA中BCC转换为FCC的21 GPa.
- 压力回收样本只显示FCC粒,表明完全的转化.
结论:
- 在EHEAs中,有序B2相的存在显著降低了B2到FCC相转换所需的压力.
- 这一发现为EHEA在极端条件下的相稳定性和机械行为提供了洞察力.
- 该研究强调了加工方法对EHEAs的高压反应的影响.
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