一种低密度钢等温压缩时组织的演化和动态再结晶  

Microstructure Evolution and Dynamic Recrystallization of a Low Density Steel during Isothermal Compression

作　　者：孙建 李景辉 黄贞益 章小峰 王东生 刘述庆 SUN Jian;LI Jinghui;HUANG Zhenyi;ZHANG Xiaofeng;WANG Dongsheng;LIU Shuqing(School of Mechanical Engineering,Tongling University,244061 Tongling,China;School of Metallurgical Engineering,Anhui University of Technology,243002 Ma'anshan,China)

机构地区：[1]铜陵学院机械工程学院,铜陵244061 [2]安徽工业大学冶金工程学院,马鞍山243002

出　　处：《材料研究学报》2024年第10期768-781,共14页Chinese Journal of Materials Research

基　　金：国家自然科学基金(51674004,51805002);安徽省高等学校自然科学研究重点项目(2022AH051760);铜陵学院自然科学研究项目(2023tlxy05,2023tlxy03,2017tlxy23);工程液压机器人安徽普通高校重点实验室(铜陵学院)开放课题资助项目(TLXYCHR-O-21YB03)

摘　　要：对一种低密度钢Fe-29.96Mn-9.56Al-1.01C在温度为850~1100℃和应变速率为0.01~10 s^(-1)条件下进行等温压缩,用OM、EBSD和TEM等手段对其表征并构建基于应变补偿的本构方程,研究这种钢在等温压缩过程中的组织演化和动态再结晶以及Z参数对其动态再结晶的影响。结果表明,低温和高应变速率有利于钢中生成细小的动态再结晶晶粒,但是再结晶不充分。应变速率的降低和温度的提高,可使这种钢的动态再结晶较为充分。低密度钢的动态再结晶与Z值有密切的关系。高温和低应变速率的变形条件有利于Z值较低的低密度钢发生再结晶和晶粒的长大。Z值处于中高值的低密度钢,其动态再结晶的晶粒细较小和保留原始带状组织,再结晶程度较低。在低密度钢的热变形过程中晶界取向差呈双峰结构,其主要动态再结晶机制是非连续动态再结晶,在各个热压缩条件下连续动态再结晶和几何动态再结晶的程度都比较低。A low-density steel Fe-29.96Mn-9.56Al-1.01C was isothermal compressed in a temperature range of 850~1100℃and strain rate range of 0.01~10 s^(-1),meanwhile,the microstructure evolution and dynamic recrystallization process of the steel were studied by OM,EBSD and TEM.On this basis,the corresponding constitutive equation of the steel is constructed based on strain compensation,and the effect of Z parameter on the dynamic recrystallization of the steel was analyzed.The results show that the conditions of low temperature and high strain rate are beneficial to the formation of fine dynamic recrystallization grains,but the recrystallization is not sufficient.In comparison,the conditions of decreasing strain rate while increasing temperature are more favorable to the completion of the dynamic recrystallization process of the steel.The Z-value has an important relationship with the dynamic recrystallization of the steel,i.e.the deformation condition of high temperature and low strain rate is conducive to the recrystallization and the grain growth for the steel with low Z-value.For the steel with middle and high Z values of,the same condition may be conductive to the formation of fine dynamic recrystallization grains,the retention of the original band-structure,and thereby a low degree of recrystallization.The grain boundary orientation difference of the steel shows a bimodal structure during thermal deformation.The main dynamic recrystallization mechanism of the steel is discontinuous dynamic recrystallization.The degree of continuous dynamic recrystallization and geometric dynamic recrystallization is weak under different thermal compression conditions.

关 键 词：材料科学基础学科 Fe-Mn-Al-C 低密度钢 等温压缩 组织演化 动态再结晶 

分 类 号：TG142.1[一般工业技术—材料科学与工程]