快速加热1045钢的动态可塑性模型高达1000°C
Steven P Mates1, Sheng-Yen Li1
1National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
概括
研究人员开发了一种新模型,用于预测金属在快速加热过程中的行为,这对于理解加工过程至关重要. 该模型捕捉了复杂的塑料反应,改进了金属切割操作的模拟.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 计算建模 计算建模
背景情况:
- 快速加热金属可以改变其机械性能,影响加工等制造工艺.
- 了解金属在极端热条件下的时间依赖的塑性反应对于准确的模拟至关重要.
研究的目的:
- 开发一种实验技术,用于测量快速加热下金属的动态流应力.
- 提出一个构成模型,准确地捕捉1045钢在快速加热条件下的流应力和硬化演变.
- 通过结合快速加热金属的行为来增强金属切割的模拟.
主要方法:
- 使用国家标准与技术研究所 (NIST) 开发的一种新技术,对动态流应力的实验测量.
- 构成模型的开发,将普雷斯顿 - 克斯 - 华莱士可塑性模型与双率灵敏度模型相结合.
- 整合了依赖应变速率的高斯函数,以考虑动态应变衰老效应.
主要成果:
- 测量结果显示,1045钢由于动态应变老化和奥氏体转化而出现复杂的热软化.
- 拟议的构成模型有效地捕捉了在快速加热下1045钢的流应力和硬化演变.
- 该模型在加工模拟中显示了与现有的1045钢的可塑性模型相比的更高的准确性.
结论:
- 开发的实验技术和构成模型为研究金属在快速加热下的行为提供了强大的方法.
- 对快速加热的金属进行准确的建模对于提高金属切割工艺的模拟准确性至关重要.
- 这些发现有助于更好地了解高延展率,高温制造环境中的材料反应.
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