这是通过原子间潜能开发和分子动力学模拟来了解Nb-Cr系统的热力学行为的第一步
Lucas A Heaton1, Adib J Samin2
1Department of Engineering Physics, Air Force Institute of Technology, Wright-Patterson Air Force Base, Dayton, 45433, USA.
Scientific reports
|June 22, 2024
概括
本研究探讨了- (NbCr) 固体溶液,发现含量增加会降低机械强度和热性能. 而C36的全方位表现出了跨温度和压力的最大热力学稳定性.
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
- 固态化学 固态化学
背景情况:
- - (NbCr) 固体溶液对其热力学性能研究不足.
- 了解这些特性对于先进的材料应用至关重要.
研究的目的:
- 为了研究不同含量的NbCr固体溶液的热力学行为.
- 评估对机械强度,热性能和结构稳定性的影响.
主要方法:
- 使用嵌入式原子模型 (EAM) 开发初步的原子间潜力.
- 在密度函数理论 (DFT) 数据上训练潜力.
- 模拟以评估机械强度,热容量,热膨胀,热导率和弹性系数.
- 对于NbCr全方位 (C14,C15,C36) 的吉布斯自由能量计算.
主要成果:
- 机械强度,热容量,热膨胀系数和热导率随着含量增加而下降.
- 弹性系数高度依赖于成分.
- 对于任何成分或温度,都没有达到Pugh脆化标准.
- 预测C36全方位是最热力学稳定的阶段,随着压力增加而变得更加稳定.
结论:
- 初步的EAM潜力提供了洞察力,但有局限性,需要进一步开发.
- 添加通常会降低NbCr固体溶液中的热力学性能.
- 支持C36结构,尽管相稳定性预测存在潜在的不准确性.
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