一种奥氏体变形应力应变集成模型

来源期刊：钢铁2011年第6期

论文作者：刘东升 李庆亮

文章页码：63 - 67

关键词：Kocks-Mecking模型； JMAK静态再结晶模型； 奥氏体热变形集成模型

Key words：Kocks-Mecking model； JMAK equation； integrated flow stress model

摘    要：介绍了预报奥氏体经多道次塑性加工时应力应变行为的集成模型。研究了试验钢加热等温过程奥氏体晶粒尺寸。在Gleeble 3800试验机上完成了系列单道次和双道次热压缩变形试验。采用Kocks-Mecking加工硬化物理模型,建立了奥氏体单道次变形过程应力应变本构关系模型。应用Johnson-Mehl-Avrami-Kolmogorov(JMAK)方程,建立了奥氏体热变形后静态再结晶动力学模型。多道次变形行为由奥氏体变形应力应变本构模型和变形结束后静态再结晶软化动力学模型描述。预报了双道次连续变形过程奥氏体的流变应力,计算结果和试验测得的结果相吻合。

Abstract: A model for predicting the constitutive deformation behaviour of austenite during multi-pass hot working was introduced.The austenite grain growth behaviour during isothermal reheating was investigated by conventional optical metallographic technique supplemented by in-situ microstructure observations employing a Confocal Scanning Laser Microscope(CSLM) for the experimental material.A series of single hit and double hit hot compression tests were conducted employing the state-of-the-art Gleeble 3800 thermo mechanical simulator.The physically based,Kocks-Mecking model has been employed to describe the deformation behaviour of austenite while the Johnson-Mehl-Avrami-Kolmogorov(JMAK) approach has been used to predict static recrystallization kinetics.The flow stress behaviour of a series of double hit independent tests was calculated showing good agreement with the experimental measurements.