在V-Ti-Co系统中,相平衡,固化微观结构和运输行为
Erhu Yan1, Zhijie Guo1, Limin Jia2
1Guangxi Key Laboratory of Information Materials, Guilin University of Electronic Technology, Guilin 541004, China.
Membranes
|September 27, 2023
概括
建立了V-Ti-Co相位图,使得能够设计出新的透合金. 合金V23.5Ti50Co26.5具有创纪录的透性,没有变脆.
科学领域:
- 材料科学 材料科学 材料科学
- 金工业是金工业的一个方面.
- 物理化学 物理化学
背景情况:
- V-Ti-Co相位图对于开发先进的透合金至关重要,但仍未确立.
- 了解相位关系是设计具有特定运输特性的材料的关键.
研究的目的:
- 使用CALPHAD方法和实验验证,构建第一个V-Ti-Co相位图.
- 根据已建立的相图设计和研究透VxTi50Co50-x合金.
- 评估这些新型合金的微观结构和运输行为.
主要方法:
- 分相图的计算 (CALPHAD) 方法用于分相图的构造.
- 阶段图的实验验证.
- 基于相位图预测的合金设计.
- 使用X射线衍射 (XRD),扫描电子显微镜 (SEM) 和能量分散光谱 (EDS) 的微结构特征.
- 气运输行为分析.
主要成果:
- 首个V-Ti-Co相位图成功构建,包括六个三元不变反应和八个相位区域.
- 设计了可透VxTi50Co50-x合金,其特定的组成 (x = 17.5-23.5) 显示出高透性.
- 合金V23.5Ti50Co26.5呈现出4.05 × 10-8mol H2 m-1s-1Pa-0.5的创纪录的透性.
- 高透性归因于增加的溶性和扩散性,受 (V,Ti) 阶段的Ti含量影响.
- V-Ti-Co 系统的透性明显高于 Nb-TiCo 和 Nb-TiNi 合金.
结论:
- 建立的V-Ti-Co相位图为设计高性能透合金提供了基础.
- VxTi50Co50-x合金,特别是那些具有TiCo相和优质结构的合金,是分离应用的有希望的候选者.
- 合金V23.5Ti50Co26.5代表了该系统中透性的新基准,为先进的技术提供了潜力.
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