发展粘性塑性构成模型,考虑加热速率对颗粒大小的影响以及热变形中的相位演变
Zheng Gao1, Shengyu Liu1, Jiatian Lin1
1School of Mechanical Engineering, Dalian University of Technology, Dalian 116024, China.
Materials (Basel, Switzerland)
|July 30, 2025
概括
在合金热成型过程中快速加热,通过改进微观结构,显著提高了组件的可成形性和性能. 这项研究将加热速率引入构成模型,提高微观结构和热流行为预测的准确性.
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:
- 合金的热成型对加热速率和温度敏感,影响相位转换,颗粒大小和位移演变.
- 这些微观结构变化直接影响合金组件的可塑性和使用性能.
研究的目的:
- 研究Ti-6Al-4V在不同的加热速率 (0.110 °C/s) 和温度 (800900 °C) 下的热流行为.
- 量化加热速度对相位转换,粒度大小和位移密度的影响.
- 开发和验证一个包含加热速率的粘性塑料构成模型,用于准确的微观结构和热流预测.
主要方法:
- Gleeble热拉伸实验,以评估热流行为.
- 电子反射衍射 (EBSD) 和X射线衍射 (XRD) 用于微观结构的表征.
- 开发一个粘性塑料构成模型和有限元素 (FE) 模拟.
主要成果:
- 较高的加热速率降低了β相转换和脱位密度,抑制了谷物的粗化并提高了可塑性.
- 构成模型实现了高预测准确度的热流行为 (92.93%) 和阶段体积分数 (94.97%).
- 快速加热的组件表现出增强的厚度均性和度强度,FE模拟显示出高预测精度 (厚度为96.96%,β阶段为92.76%).
结论:
- 加热速率是Ti-6Al-4V热成型中的关键参数,直接影响微观结构和机械性能.
- 开发的构成模型准确地预测了加热速率对热成型过程的影响.
- 使用快速加热的优化热成型策略可以带来优越的组件质量和性能.
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