新型热冲压高强钢22MnB5(Nb&V)的热变形本构关系  

Thermal deformation constitutive relationship of new type high strength hot stamping steel 22MnB5(Nb&V)

作　　者：童坤 韩先洪[1] 崔振山[1] TONG Kun;HAN Xian-hong;CUI Zhen-shan(National Engineering Research Center of Die&Mold CAD,Shanghai Jiao Tong University,Shanghai 200030,China)

机构地区：[1]上海交通大学模具CAD国家工程研究中心

出　　处：《塑性工程学报》2019年第6期256-262,共7页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(U1564203)

摘　　要：为了研究新型热冲压高强钢22MnB5 (Nb&V)高温流变力学行为,采用热模拟试验机Gleeble-1500D,在550~850℃温度区间,分别以0. 1、0. 5、1和5 s-1的应变速率进行等温单向拉伸实验,得到相应实验条件下的真应力-应变曲线。综合考虑应变量、加工硬化、应变速率和温度等因素的影响,采用Johnson-Cook模型描述了流变应力方程,将建立的新型高强钢本构模型应用于热冲压数值模拟中,得到板料变形过程的载荷变化曲线,并与实验数据进行对比表明,该模型能准确描述不同变形条件下的流变应力-应变曲线,较好地再现了变形过程中的加工硬化、应变速率强化以及温度软化等效应。To study the flow behavior of a new type high strength hot stamping steel 22MnB5(Nb&V)at high temperature,isothermal tensile tests were carried out by using thermo-mechanical simulator Gleeble-1500D at strain rate of 0.1,0.5,1 and 5 s-1 and temperature of 550-850℃,respectively.The true stress-strain curves were obtained under the corresponding conditions.Considering the effects of strain,work hardening,strain rate and temperature,the Johnson-Cook model was used to describe the flow stress equation of the material at hot stamping temperature.The new established high-strength steel constitutive model was applied to the numerical simulation of hot stamping,and the load variation curve of plate deformation was obtained.Compared with the experimental data,the model can accurately describe the flow stress curves under different deformation conditions,and reproduce the effects of work hardening,strain rate strengthening and temperature softening in the deformation process.

关 键 词：22MnB5(Nb&V) 热冲压 本构关系 Johnson-Cook模型 

分 类 号：TG142.13[一般工业技术—材料科学与工程]