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在金属玻璃中,组合复杂性缓冲器具有自由体积灵敏度和状流量
Anurag Bajpai1, Jaemin Wang1, Dierk Raabe1
1Max Planck Institute for Sustainable Materials, Düsseldorf, Germany.
概括
在金属玻璃 (MGs) 中添加铜-等元素会降低其对加工条件的敏感性. 这种复杂的构成增强了机械性能和稳定性,从而产生了高性能材料.
科学领域:
- 材料科学 材料科学 材料科学
- 计算材料科学科学 计算材料科学
- 合金设计设计 合金设计
背景情况:
- 处理历史显著影响金属玻璃 (MGs) 的性能.
- 构成复杂度对MG的结构和机制对冷却速率的敏感性的影响尚未完全理解.
研究的目的:
- 研究铜 (Cu-Zr) 基金属玻璃的复杂性增加如何影响其结构和机械性能.
- 确定组合复杂性是否可以使MG对制造过程中冷却速率的变化变得不敏感.
主要方法:
- 采用 Cu-Zr,Cu-Zr-Al 和 Cu-Zr-Al-Ti 系统的大规模分子动力学模拟,在广泛的冷却速率 (10^1110^15 K·s^-1) 上进行了玻璃化.
- 采用球形纳米沉积来探测机械性能.
- 通过激素-沃罗诺伊模块化分析了原子自由体积,并通过福克-兰杰D^2_min场量化了非亲系重排.
主要成果:
- 构成复杂性的增加缩小了自由体积分布,并降低了对冷却速度的敏感性.
- 构成复杂性抑制了在快速和缓慢的冷却速度下获得的特性之间的差异.
- 观察到增强的硬度,模量和弹性回收,复杂性增加,同时减少了和剪切转换区 (STZ) 密度.
结论:
- 构成复杂性作为一个定量杆来实现耐加工,高性能金属玻璃.
- 这些发现使配置效应与合金设计中的和结构因素相协调.
- 构成复杂度较高的基于Cu-Zr的MG显示出更好的中短距离原子秩序和稳定性.
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