P91耐热钢热变形行为及其流变应力本构方程  

Hot Deformation Behavior of P91 Heat-resistant Steel and Related Flow Stress Constitutive Equations

作　　者：张宝惠[1] 曹金荣[1] 肖功业[1] 何彪[1] 王国亮[1] 赵庆全[1] 张俊萍[1] 

机构地区：[1]天津钢管集团股份有限公司技术中心,天津300301

出　　处：《钢管》2012年第1期23-28,共6页Steel Pipe

摘　　要：基于位错反应理论和Avrami方程,建立了包含动态应变时效影响的动态回复与动态再结晶的两阶段本构方程。采用Gleeble3500热模拟试验机对P91耐热钢进行热压缩试验,获得了950～1200℃、0.01～10s-1条件下的P91耐热钢真应力-真应变曲线。利用试验获得的流变应力数据,采用非线性拟合确定了P91钢本构方程中的材料常数。模型的计算结果表明,计算曲线与试验曲线吻合得较好,所建立的本构方程可应用于预测P91钢在950～1200℃、0.01～10s-1条件下热加工变形的流变应力。Based on the dislocation reaction theory and the Avrami equation,a two-stage constitutive equation model is developed to describe dynamic recovery and dynamic re-crystallization,which couple the effect of the dynamic strain aging in the alloy during hot deformation. With the Gleeble 3500 simulation testing machine,uni- axial thermocompression tests to the P91 heat resistant steel are carried out under the conditions of 950～1 200 ℃ and 0.01～10 s-1,which results in the true stress-true strain curves thereof. In combination with the experimental data concerning the flow stress of the P91 steel,the material parameters of the said constitutive equation are determined by using the non-linear dada-fitting method. The calculation result from the constitutive equation shows that the calculated curves are in compliance with the experimental curves,which means that the constitutive equation of the P91 steel is capable of predicting the flow stresses of the steel being deformed at the hot working conditions of temperature ranging from 950 ℃ to 1 200 ℃,and strain rating from 0.01 s^-1 to 10 s^-1.

关 键 词：P91耐热钢 热变形 位错 本构方程 热压缩试验 流变应力 

分 类 号：TG142.73[一般工业技术—材料科学与工程]