摘要
利用Gleeble-3500热模拟试验机,在850~1180℃温度下,以0.001~20 s-1的应变速率对300M高强钢进行变形量为60%的热压缩变形试验,对其在不同变形条件下的变形行为进行研究。结果表明,300M高强钢的变形行为与变形参数密切相关,变形温度越高,应变速率越低,越有利于动态再结晶的发生。基于试验数据,建立了Arrhenius双曲正弦方程中Q,A,n,α与真应变的本构关系,从而进一步建立了包含变形温度、应变速率及应变在内的300M高强钢的高温变形本构方程。为了验证该本构方程的正确性,对应力计算值与试验值进行了对比及平均误差分析,最大误差为14.2%,但整体均控制在10%以下。分析表明,应用所建立的本构方程得到的应力计算值与试验值吻合较好。
Hot compression deformation tests whose height reduction is 60% were conducted on 300M high strength steel by using a Gleeble -3500 thermal simulator with deformation temperatures ranging from 850 ℃ to 1180 ℃ and strain rates ranging from 0. 001 s- 1 to 20 s-1. Investigation was conducted on deformation behavior of 300M steel under different deformation conditions. The results show that the deformation behavior of 300M steel is closely related to the deformation parameters. The dynamic recrystallization occurs more easily if the deformation temperature is higher and the strain rate is lower. The constitutive relationships between Q, A, n, α in hyperbolic sine equations of Arrhenius - type and true strain were established based on experimental data, so the constitutive equation of 300M high strength steel at high temperature including deformation temperature, strain rate and strain was further established. In order to evaluate the accuracy of constitutive equation, comparison and mean error analysis of flow stress between the experimental data and calculated results were conducted. The worst case is the error of 14. 2%, but the errors are below 10% on the whole. The analysis shows that the flow stress values calculated by the established constitutive equation are coincident with experimental data well.
出处
《锻压技术》
CAS
CSCD
北大核心
2014年第8期109-114,共6页
Forging & Stamping Technology
基金
国家科技重大专项"高档数控机床与基础制造装备"(2012ZX04010-081)
关键词
300M高强钢
热压缩变形
本构方程
误差分析
300M high strength steel
hot compression deformation
constitutive equation
error analysis
