具有广泛应变速率和温度效应的化OFHC的构成模型:结合脱位动力学和规范化微观结构尺寸演变
Mengwen Xu1, Qiangqiang Xiao1, Xudong Zu1
1School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
Materials (Basel, Switzerland)
|October 14, 2023
概括
一个新的构成模型通过将其与微观结构演变联系起来,解释了面中心立方 (FCC) 金属的流应力快速增加,超越了现有的模型.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 固体力学 固体力学是什么
背景情况:
- 面中心立方体 (FCC) 金属显示流应力在10^4s^-1附近急剧增加.
- 现有的模型很难准确地捕捉这种塑性变形,或者依赖于不连续的片式函数.
- 这种突变现象在当前模型中缺乏明确的物理机制表示.
研究的目的:
- 为FCC金属提出一个连续的,半经验性的物理构成模型.
- 归因于微观结构进化的应变率灵敏度的突然变化.
- 准确地描述应变率敏感性在固定应变下的突变行为.
主要方法:
- 开发了一种连续的半实证物理构成模型.
- 集成的微观结构尺寸演变和脱位运动滑动机制.
- 在广泛的应变速率 (10^-4-10^6 s^-1) 和温度 (77-1096 K) 中验证了模型.
主要成果:
- 拟议的模型有效地描述了FCC金属中应变率敏感性的突变行为.
- 预测结果显示相对误差一般在OFHC的实验值的±10%以内.
- 与MTS,NNL,PTW,JC和MR模型相比,该模型表现出卓越的性能.
结论:
- 微结构进化特征是理解流应力灵敏度突然变化的关键.
- 新模型提供了准确的预测,并优于OFHC塑性变形的现有模型.
- 这些发现为选择工程模型提供了洞察力,并促进了对FCC金属行为的理解.
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