先进高强贝氏体钢过冷奥氏体变形应力-应变模型  

Stress-strain model of undercooled austenite deformation for advanced high-strength bainitic steel

作　　者：李群芳 任可 简楚 梅建军 黄睿希 王礼凡 胡海江[1] LI Qun-fang;REN Ke;JIAN Chu;MEI Jian-jun;HUANG Rui-xi;WANG Li-fan;HU Hai-jiang(The State Key Laboratory of Refractories&Metallurgy,Wuhan University of Science&Technology,Wuhan 430081,China)

机构地区：[1]武汉科技大学省部共建耐火材料与冶金国家重点实验,湖北武汉430081

出　　处：《塑性工程学报》2025年第2期157-162,共6页Journal of Plasticity Engineering

基　　金：武汉市知识创新专项(2023010201010133);大学生创新创业训练计划项目(S202310488058)。

摘　　要：以先进高碳高强贝氏体钢为对象,在Gleeble-3500热模拟机上进行奥氏体化预处理和热压缩实验,变形温度范围为400~600℃,变形基体组织为过冷奥氏体,通过分析应力-应变曲线和加工硬化指数,并基于KME模型,综合考虑位错湮灭系数k_(2)、应变速率敏感指数m与变形温度、应变之间的定量关系,揭示了变形温度和应变对模型中各参数的影响规律。结果表明,k_(2)与变形温度密切相关,中、低温变形时,k_(2)随着变形温度的增加呈现先减小后增大的趋势;m与变形温度和应变有关,随着变形温度和应变的增加而减小。最终,模型预测值与实验值对比结果表明,采用建立的m-ε和k_(2)-T模型预测先进高强贝氏体钢过冷温奥氏体流变应力效果较好。Taking advanced high-carbon high-strength bainitic steel as the research object,the austenitization pretreatment and hot compression experiments were carried out on Gleeble-3500 thermal simulator,and the deformation temperature range is 400-600℃,the microstructure of deformed matrix is undercooled austenite.By analyzing the stress-strain curve and work hardening exponent,and based on the Kocks-Mecking-Estrin(KME)model,the quantitative relationship between dislocation annihilation coefficient k_(2),strain rate sensitivity exponent m and deformation temperature,strain is comprehensively considered to reveal the influence of deformation temperature and strain on each parameter in the model.The results indicate that k_(2) is closely related with the deformation temperature,k_(2) decreases first and then increases with the increase of deformation temperature during the deformation at medium and low temperature;m is related with deformation temperature and strain,m decreases with the increase of the deformation temperature and strain.Finally,the comparison results between predicted values and experimental values show that the effects using the established m-εand k_(2)-T models to predict the flow stress of undercooled austenite in advanced high-strength bainitic steels are good.

关 键 词：高强贝氏体钢 奥氏体预变形 流变应力 位错 模型 

分 类 号：TG142[一般工业技术—材料科学与工程]