在7B50合金中的热变形行为和动态软化机制
Ming Li1, Yong Li2,3, Yu Liu2,3
1School of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China.
Materials (Basel, Switzerland)
|August 26, 2023
概括
这项研究研究了7B50合金的热变形,揭示了动态软化机制,如动态回收和动态再结晶,取决于Zener-Hollomon参数. 最佳的热加工发生在410-460°C之间.
科学领域:
- 材料科学 材料科学 材料科学
- 金工业是一种金工业.
背景情况:
- 了解热变形行为对于优化金属加工至关重要.
- 7B50合金是一种高强度材料,用于苛刻的应用.
研究的目的:
- 为了研究7B50合金的热变形行为和动态软化机制.
- 建立Zener-Hollomon参数方程并开发热处理图.
- 确定最佳的热工作区域,并将微观结构演变与变形参数相关联.
主要方法:
- 同热压缩实验是在320-460°C的温度和0.001-1.0秒-1.0秒的应变率下进行的.
- 分析了流量曲线,以建立Zener-Hollomon (Z) 参数方程.
- 使用动态材料模型开发热处理图.
- 电子背散衍射 (EBSD) 用于微观结构分析.
主要成果:
- 建立了Zener-Hollomon参数方程,热处理地图确定了410-460°C和0.01-0.001s-1.1的最佳工作区域.
- 动态软化机制和微观结构的演变被发现强烈依赖于Z参数.
- 动态恢复 (DRV) 在lnZ ≥20时占主导地位.
- 不连续动态再结晶 (DDRX) 在15 < lnZ < 20中占主导地位,随着lnZ的下降,粒径和百分比增加.
- 几何动态再结晶 (GDRX) 和连续动态再结晶 (CDRX) 机制在lnZ ≤15时共存.
结论:
- 该研究成功地描述了7B50合金的热变形行为.
- 在Zener-Hollomon参数和主要的动态软化机制 (DRV,DDRX,GDRX,CDRX) 之间建立了明确的相关性.
- 这些发现为优化7B50合金的热加工过程提供了关键数据,以实现所需的微观结构和特性.
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