通过激光粉床融合产生的耐火金属的微观结构和特性
Jinguo Ge1,2,3, Heming Wu1, Hongsen Liu3
1Institute of Semiconductors, Guangdong Academy of Sciences, Guangzhou 510650, China.
Materials (Basel, Switzerland)
|August 28, 2025
概括
(W) 的激光粉床融合显示出异构性质. 水平和垂直平面的微观结构和裂导致硬度和耐磨性不同,影响零件性能.
科学领域:
- 材料科学
- 添加剂制造
- 金属工程
背景情况:
- 激光粉床融合 (LPBF) 是生产金属组件的关键增材制造技术.
- (W) 具有独特的特性,使其适用于高性能应用.
- 了解LPBF制造材料的异构性对于优化性能至关重要.
研究的目的:
- 通过LPBF制造的纯的异构机械性能和微观结构特性.
- 分析内部缺陷及其对水平和垂直平面材料行为的影响.
- 将微观结构,缺陷和机械特性与磨损机制相关联.
主要方法:
- 使用激光粉床融合 (LPBF) 制备纯元件.
- 在水平和垂直平面上对颗粒,缺陷 (裂) 和颗粒边界进行微结构分析.
- 机械测试包括硬度和耐磨性测量.
- 在不同的测试条件下分析磨损机制.
主要成果:
- 通过LPBF加工,可以在垂直方向上产生柱状W粒,在水平平面上产生近等轴的粒.
- 主要沿着高角粒边界 (HAGB) 传播的裂,特别是在水平平面.
- 由于裂纹增加,水平平面的硬度和耐磨性明显低于垂直平面.
- 磨损机制从分层和磨损 (垂直) 转变为磨损和轻微的粘合性磨损 (水平).
结论:
- 在LPBF-W中硬度和耐磨性的异型行为主要是由横向和垂直平面之间的微观结构变化和裂分布驱动的.
- 优化LPBF工艺参数对于减轻裂纹形成和提高所有方向的机械性能至关重要.
- 这些发现为设计和制造具有针对特定应用的异构性质的组件提供了关键的见解.
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