Fe-Mn-Al-Ni-C系低密度钢热变形行为和热加工图的研究  

Study on hot deformation behavior and hot working diagram of Fe-Mn-Al-Ni-C low-density steel

作　　者：夏博 王忠军[1] 吴伟平 庞启航 李维娟[1] XIA Bo;WANG Zhongjun;WU Weiping;PANG Qihang;LI Weijuan(School of Materials and Metallurgy,University of Science and Technology Liaoning,Anshan 114051,China)

机构地区：[1]辽宁科技大学材料与冶金学院,辽宁鞍山114051

出　　处：《辽宁科技大学学报》2024年第5期337-345,394,共10页Journal of University of Science and Technology Liaoning

基　　金：鞍钢海洋装备用金属材料及其应用国家重点实验室-辽宁科技大学联合基金资助项目(HGSKL-USTLN(2020)05)。

摘　　要：采用MMS-200热模拟试验机对Fe-15Mn-15Al-5Ni-1C低密度钢在变形温度(T)为1050~1200℃和应变速率(ε̇)为0.01~0.5 s^(-1)的条件下进行热压缩实验。基于真应力-应变曲线,结合Arrhenius双曲正弦本构方程,通过多元线性回归分析获得热激活能Q、结构因子A及材料常数n和α对应变的响应规律,建立流变应力(σ)与应变量(ε)、T和ε̇之间的Arrhenius本构模型;建立了输入参数为T、ε̇、ε和输出参数为σ的BP(Back propagation)神经网络本构模型。对比发现:BP神经网络本构模型具有更高的预测精度,平均相对误差仅为4.71%。此外,建立了实验钢的热加工图,发现高应变速率易导致实验钢热变形失稳。结合显微组织动态再结晶程度,确定实验钢适宜热加工区域为:变形温度1120~1150℃和应变速率0.01~0.1 s^(-1)。The MMS-200 thermal simulation test machine was used to conduct hot compression experiments on Fe-15Mn-15Al-5Ni-1C low-density steel under deformation temperature(T)of 1050~1200℃and strain rate(ε̇)of 0.01~0.5 s^(-1).Based on the true stress-strain curves and combined with the Arrhenius hyperbolic sine constitutive equation,the response laws of thermal activation energy Q,structural factor A,and material constants n andαto strain were obtained through multiple linear regression analysis,thus establishing an Arrhenius constitutive model between flow stress(σ)and strain variables(ε),T,ε̇;and meanwhile,a BP neural network constitutive model was established with input parameters T,ε̇,ε,and output parameterσ.It is found that the prediction accuracy of BP neural network constitutive model is higher,and the average relative error is only 4.71%.In addition,a few process maps of the experimental steel were established,finding that the higher strain rates can easily lead to thermal deformation instability of experimental steel.Based on the dynamic recrystallization degree of the grains,the suitable hot working area for the experimental steel was determined to be a deformation temperature of 1120~1150℃and a strain rate of 0.01~0.1 s^(-1).

关 键 词：Fe-Mn-Al-Ni-C低密度钢 热压缩变形 本构模型 热加工图 

分 类 号：TG142.3[一般工业技术—材料科学与工程]