哈斯特洛伊C276合金的热变形行为:微观结构变化和构成模型
Daoguang He1,2, Shibing Chen1,2, Yongcheng Lin1,2
1School of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China.
Materials (Basel, Switzerland)
|September 28, 2023
概括
这项研究研究了Hastelloy C276合金.
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:
- 了解像Hastelloy C276这样的超级合金的高温机械行为,对于优化制造工艺至关重要.
- 热变形显著影响金属合金的微观结构和流动特性.
- 准确的流动行为预测对于过程模拟和质量控制至关重要.
研究的目的:
- 在同热热压缩过程中分析哈斯特洛伊C276的微结构演变和流动行为.
- 研究温度和拉伸率对变形机制的影响.
- 开发和比较Hastelloy C276流动行为的预测模型.
主要方法:
- 使用Gleeble-3500热模拟器 (1000-1150°C,0.01-10秒-1) 的同热变形实验.
- 通过传输电子显微镜 (TEM) 和电子反射散射衍射 (EBSD) 进行微结构分析.
- 开发一个基于物理的 (PB) 构成模型和一个粒子群优化 (PSO) 优化的长短期记忆 (LSTM) 模型.
主要成果:
- 热压缩参数显著影响Hastelloy C276的微观结构和流动行为.
- 增加的应变速率促进应变硬化 (SH) 并增加真正的应力.
- 高温导致动态恢复 (DRV) 和动态再结晶 (DRX),减少真正的压力.
结论:
- 与PB模型相比,LSTM模型在预测Hastelloy C276流动行为方面表现出卓越的准确性.
- 微结构进化,包括SH,DRV和DRX,决定了合金对热变形的反应.
- 优化的LSTM模型为超级合金中精确的流量应力预测提供了有希望的方法.
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