热变形对低碳贝氏体钢显微组织的影响EBSD研究  

EBSD Study of the Effect of Hot Deformation on Low Carbon Bainitic Structure

作　　者：文新理[1] 张福多[2] 曲晓东[2] WEN Xinli;ZHANG Fuduo;QU Xiaodong(Beijing Beiye Functional Materials Corporation,Beijing 100192;Angang Steel Co.,Ltd,Anshan 114001)

机构地区：[1]北京北冶功能材料有限公司,北京100083 [2]鞍钢股份有限公司,鞍山114001

出　　处：《金属材料研究》2021年第2期10-15,共6页Research on Metallic Materials

摘　　要：在Gleeble-1500热模拟试验机上通过热压缩试验研究了变形温度(DT)和变形量对低碳贝氏体钢显微组织的影响,利用EBSD技术分析了不同条件下的显微组织。在给定的热变形条件下,贝氏体组织由粒状贝氏体(GB)、板条贝氏体(LB)和少量针状铁素体(AF)组成,变形温度和变形量对相变动力学、相变开始温度(B)和贝氏体组织结构类型有重要影响。随着变形温度从810℃降低至730℃,相变开始温度由585℃提高至595℃。当变形量为0%和20%时,显微组织由GB、LB和少量AF组成,当变形量为40%时,粗大的LB和GB消失,只有AF和M/A(马奥岛)。当变形量从0%提高至40%,有效晶粒尺寸从4μm降低至2μm,大角度晶界(HGB)的比例由48%提高至57%。The effect of deformation temperature(DT)and thickness reduction on the bainitic structure was investigated under various test conditions by using hot compression on a Gleeble-1500 thermo-mechanical simulation machine,and electron back scattering diffraction(EBSD)technique.In the case of the bainitic structure consisting of granular bainite(GB),lath bainite(LB)and a little ferrite(AF)under the given deformation conditions,DT and thickness reduction have remarkable effect on the transformation kinetics,starting temperature(B)of bainite fast transformation,and the type of bainitic structure.With the decreasing of DT from 810℃ to 730℃,the starting temperature of transformation B increase from 585℃ to 595℃.When the thickness reduction was 0%and 20%,the microstructure consists of GB,LB and a little AF,whereas as the thickness reduction increase to 40%,large grain size of LB and GB disappear,and only AF and M/A remained.With the thickness reduction increases from 0%to 40%,the effective grain size decreases from 4μm to 2μm,and the fraction of HGB increases from 48%to 57%.

关 键 词：EBSD 热变形 显微组织 贝氏体组织 相变动力学 相变开始温度 

分 类 号：TG1[金属学及工艺—金属学]