一个基于内部状态变量的持续动态再结晶模型,用于热变形TC18合金
Gui-Cheng Wu1,2, Yong-Cheng Lin1,2, Miao Wan1,2
1School of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China.
Materials (Basel, Switzerland)
|August 29, 2024
概括
在热成型下研究了TC18合金中的连续动态再结晶 (CDRX). 一个内部状态变量模型准确地预测了流应力和微观结构的演变,显示了在更高的应变率下过渡到更细的基结构.
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:
- 连续动态再结晶 (CDRX) 在热成型过程中显著影响合金微结构.
- 具有中等至高堆叠故障能量的TC18合金,在变形下表现出复杂的微观结构演变.
研究的目的:
- 在热变形过程中调查TC18合金的流应力和CDRX行为.
- 开发和验证基于内部状态变量 (ISV) 的CDRX模型.
主要方法:
- 在TC18合金上的热变形实验.
- 微结构分析侧重于谷物边界演变 (LAGBs到HAGBs).
- 基于ISV的CDRX模型的开发,包括位移密度,温度和误导.
主要成果:
- 变形引发了新的低角度粒度边界 (LAGBs),后转变为高角度粒度边界 (HAGBs).
- 基于ISV的模型在预测真实应力方面显示出高精度 (R=0.989,RAAE=6.69%,RMSE=4.78 MPa).
- 模型准确地预测了颗粒尺寸的减小,而延展率更高,温度更低,表明向持续再结晶的基结构的转变.
结论:
- 开发的基于ISV的模型有效地捕捉了TC18合金中的CDRX现象.
- 在特定的加工条件下,微结构从粗粒度过渡到更细的,持续再结晶的基结构.
- 该模型提供了一种定量工具,用于预测热成型期间的微结构演变.
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