55SiMnMo贝氏体钢高温流变应力本构方程  

Constitutive Equation for High Temperature Flow Behavior of 55SiMnMo Bainite Steel

作　　者：闫涛[1,2] 于恩林[1,2] 赵玉倩[3] 

机构地区：[1]燕山大学国家冷轧板带装备及工艺工程技术研究中心,河北秦皇岛066004 [2]燕山大学机械工程学院,河北秦皇岛066004 [3]东北大学秦皇岛分校控制工程学院,河北秦皇岛066004

出　　处：《钢铁》2013年第9期58-63,70,共7页Iron and Steel

摘　　要：采用Gleeble-3500热模拟试验机对55SiMnMo贝氏体钢进行了热压缩试验,得到了其在变形温度为950-1150℃和应变速率为0.01-10s-1条件下的高温流变应力行为。试验结果表明,峰值应力随变形温度的降低和应变率的提高而增大;当应变速率ε为0.01和0.1s-1,变形温度t≥1 000℃时,发生动态再结晶。基于试验结果,充分考虑了热变形工艺参数(应变、应变速率和变形温度)对流变应力的影响,建立了一种考虑应变速率补偿的高温流变应力本构方程。通过对该本构方程预测得到的流变应力值和试验值对比,验证了模型的准确性。The high temperature flow behavior of 55SiMnMo bainite steel was studied by hot compression test at temperatures of 950-1100℃ with strain rates of 0. 01-10 s-1 using Gleeble-3500 thermal-simulation machine. Experimental results show that peak stress increases with decreasing of deformation temperature and increasing of strain rate; dynamic recrystallization of 55SiMnMo steel occurs with strain rate ε=0.01～10s-1 and ε = 0.1 s -1 , deformation temperature t≥l 000 ℃. According to the experimental results, the influence of hot deformation processing parameter （strain, strain rate and deformation temperature） on flow stress was analyzed. A constitutive equation of 55SiMnMo bainite steel during high temperature deformation was established to describe the stress-strain relationship by considering compensation of strain rate. The reliability of the model was verified by the comparison between the predicted flow stress curves by the model and the experimental data.

关 键 词：55SiMnMo钢 单向热压缩 热变形行为 应变速率补偿 

分 类 号：TG142.15[一般工业技术—材料科学与工程]