动态球状化机制及其方向依赖性Ti-6Al-2Mo-2V-1Fe合金在subtransus热变形期间的方向依赖性
Jinyang Ge1, Xiaodong Zhan1,2, Chao Li2
1State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China.
Materials (Basel, Switzerland)
|September 9, 2023
概括
这项研究揭示了合金微结构如何在热变形过程中发生变化. 最佳的球化发生在特定的晶体学方向被激活时,指导合金加工.
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.
- 机械工程 机械工程
背景情况:
- 了解合金中的微结构演变对于优化机械性能至关重要.
- 亚横热变形显著影响合金的相形态和性质.
- 阿尔法相的球化会影响合金的可塑性和性能.
研究的目的:
- 调查Ti-6Al-2Mo-2V-1Fe合金在热变形过程中的动态球化机制.
- 为了确定球形化对晶体学倾斜的方向依赖.
- 为合金工艺设计和微观结构控制提供见解.
主要方法:
- 热压缩测试在780-880°C的温度范围内进行,应变速率为0.001-0.1s-1.1.
- 微结构分析使用扫描电子显微镜 (SEM),电子反射散射衍射 (EBSD) 和传输电子显微镜 (TEM).
- 确定了微观结构特征 (面积比,粒度边界) 和变形参数之间的相关性.
主要成果:
- 随着温度的增加和延展率的下降,阿尔法相的面积比率下降,在880°C/0.001s−1.1.时达到2.05的最低值.
- 高角粒边界 (HAGBs) 的形成与球化相反,这表明HAGBs对于这个过程并不重要.
- 阿尔法相接口是通过高温的脱位演变和低温的双边界形成的.
- 当晶体定向倾斜 (θ) 在45°至60°之间时,球状化最有利,激活了镜和基底滑动系统.
结论:
- 该研究阐明了Ti-6Al-2Mo-2V-1Fe合金中的动态球化机制及其方向依赖.
- 变形温度,应变速率和结晶学定向对球化产生了重大影响.
- 这些发现为定制合金微结构和优化制造工艺提供了宝贵的指导.
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