理论预测和Zr3AC2 (A = Cd,Sb) 阶段的实验合成
Jia Luo1, Fengjuan Zhang1, Bo Wen1
1Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, China.
Materials (Basel, Switzerland)
|April 13, 2024
概括
这项研究通过理论和实验方法证实了新的Zr3CdC2和Zr3SbC2 MAX阶段的存在. 这些稳定,可加工的材料为先进材料应用开辟了新的途径.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 计算材料科学科学 计算材料科学
背景情况:
- 马克斯相是一种三元碳化物和化物的类,具有显著的研究和应用潜力.
- 合成含有 (Cd) 和 (Sb) 的MAX相具有相当大的挑战.
- 由于其独特的元素组成,Zr3AC2 (A = Cd,Sb) MAX阶段特别有趣.
研究的目的:
- 理论预测和实验合成新的312 MAX阶段:Zr3CdC2和Zr3SbC2.
- 为了研究这些新的MAX相的热,热力学和机械稳定性.
- 探索它们的机械特性,包括弹性模块和维克斯硬度,并了解影响它们的因素.
主要方法:
- 第一原则计算被用于理论预测和财产调查.
- 使用形成能量,声子分散和Born-Huang标准来评估稳定性.
- 通过火花等离子体烧结实现了实验合成.
- 使用扫描电子显微镜 (SEM) 和能量分散式X射线光谱 (EDS) 分析了微观结构和组成.
主要成果:
- 证实了Zr3CdC2和Zr3SbC2 MAX阶段的存在.
- 这两个阶段都表现出极好的热,热力学和机械稳定性.
- 理论弹性模块计算为Zr3CdC2的162.8 GPa,而Zr3SbC2.2的164.3 GPa.
- 低维克尔硬度值 (Zr3CdC2的5.4 GPa,Zr3SbC2的4.3 GPa) 表明了良好的可加工性.
- 在特定的温度下,成功合成了含有这些相的复合材料.
- 确定了Zr:Cd/Sb:C (3:1.5:1.5) 的最佳摩尔比率.
- SEM/EDS证实了典型的分层微观结构.
结论:
- 该研究成功证实了Zr3CdC2和Zr3SbC2 MAX阶段的存在和稳定性.
- 这些材料表现出有前途的机械性能,包括良好的可加工性,用于潜在的应用.
- 这些发现为进一步研究和开发含有Cd和Sb的MAX相提供了基础.
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