40CrMnMoA合金钢的动态再结晶临界应变模型  

Dynamic recrystallization critical strain model of 40CrMnMoA alloy steel

作　　者：刘丙旗 陈学文[1] 周旭东[1] 尹丹青[1,2] 皇涛 LIU Bing-qi;CHEN Xue-wen;ZHOU Xu-dong;YIN Dan-qing;HUANG Tao(School of Materials Science and Engineering,Henan University of Science and Technology,Luoyang 471000,China;Longmen Laboratory,Luoyang 471000,China)

机构地区：[1]河南科技大学材料科学与工程学院,河南洛阳471000 [2]龙门实验室,河南洛阳471000

出　　处：《材料热处理学报》2023年第8期186-193,共8页Transactions of Materials and Heat Treatment

基　　金：国家重点研发计划项目(2020YFB2008400)。

摘　　要：为了控制40CrMnMoA合金钢在热变形后的微观组织,研究了该合金钢的动态再结晶行为。采用Gleeble-1500D热-机械模拟压缩试验机在900~1200℃、0.005~5 s^(-1)条件下对40CrMnMoA合金钢进行了高温压缩试验,获得了该合金钢的应力应变曲线。基于试验数据,确定了该合金钢的Zener-Hollomon参数(Z参数)及变形激活能Q=325397.448 J/mol。结果表明:在低lnZ(<30)条件下40CrMnMoA合金钢的应力应变曲线有明显的下降趋势,lnZ越小,该特点越明显,是典型的动态再结晶型曲线。在高lnZ(>30)条件下40CrMnMoA合金钢的应力随着应变的增加不断上升,呈现出典型的动态回复特性。基于试验数据,计算了40CrMnMoA合金钢的加工硬化率θ,通过分析低ln Z条件下的θ-σ曲线,获得了40CrMnMoA合金钢的临界应变和峰值应变,建立了对应的动态再结晶临界应变模型为ε_(c)=0.0010988Z^(0.19324)。In order to control the microstructure of 40CrMnMoA alloy steel after hot deformation,the dynamic recrystallization behavior of the alloy steel was studied.The high temperature compression test of the 40CrMnMoA alloy steel was carried out by using Gleeble-1500D thermo-mechanical simulation compression tester at the conditions of deformation temperature of 900-1200℃ and strain rate of 0.005-5 s^(-1),and the stress-strain curves of the alloy steel were obtained.Based on the experimental data,the Zener-Hollomon parameter(Z parameter)and deformation activation energy Q(325397.448 J/mol)of the alloy steel were determined.The results show that the stress-strain curves of the 40CrMnMoA alloy steel has an obvious downward trend under the condition of low lnZ(<30),the smaller the lnZ is,the more obvious the characteristic is,which is a typical dynamic recrystallization curve.Under the condition of high lnZ(>30),the stress of the 40CrMnMoA alloy steel increases with the increase of strain,showing typical dynamic recovery characteristics.Based on the experimental data,the work hardening rate θ of the 40CrMnMoA alloy steel is calculated,by analyzing the θ-σ curve under the condition of low lnZ,the critical strain and peak strain of the 40CrMnMoA alloy steel are obtained,and the corresponding dynamic recrystallization critical strain model is established:ε_(c)=0.0010988Z^(0.19324).

关 键 词：40CrMnMoA合金钢 高温压缩 Z参数 动态再结晶 临界应变模型 

分 类 号：TG142.3[一般工业技术—材料科学与工程]