通过相稳定性调来限制过渡金属碳化物的位移运动
H W Hugosson1, U Jansson, B Johansson
1Condensed Matter Theory Group, Department of Physics, Uppsala University, Box 530, S-751 21 Uppsala, Sweden. hakan.hugosson@fysik.uu.se
概括
一种新方法通过创建可调节层堆叠的多相化合物来提高材料硬度. 这种方法抑制了脱位运动,从而显著提高了先进涂料的材料强度.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 计算材料科学科学 计算材料科学
背景情况:
- 多层涂层对于增强材料性能至关重要.
- 硬过渡金属碳化物在技术上很重要,但在硬度增强方面存在局限性.
- 传统的超级网格在硬度机制中提供了有限的可调性.
研究的目的:
- 提出和研究一种用于增强多层涂料硬度的新机制.
- 探索创建具有可调节结构的多相/多类型化合物的潜力.
- 为了证明如何控制层堆叠可以抑制脱位传播增加硬度.
主要方法:
- 使用第一原则计算来研究过渡金属碳化物中竞争结构之间的能量差异.
- 采用计算方法来预测多相/多类型化合物的形成.
- 分析随机或可控制层叠加序列对材料性能的影响.
主要成果:
- 证明合适的合金使过渡金属碳化物中竞争结构之间的能量差异变小或可调节.
- 表明这种可调性使得可以创建可控制的层叠加的多相/多类型化合物.
- 确定了具有不同滑翔系统的结构之间的高密度接口强烈抑制了脱位传播.
结论:
- 拟议的机制为大大提高材料硬度提供了一条途径.
- 现代薄膜技术可用于沉积这些新型多层材料.
- 这种方法为传统的超级格子提供了更灵活的化学替代方案,用于增强硬度.
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