低碳钢热变形过程中铁素体的织构形成规律  

Orientational analysis of warm-compressed ferrite in a low carbon steel by means of orientation mapping

作　　者：杨平[1] 常守海[2] 孙祖庆[3] 

机构地区：[1]北京科技大学材料科学与工程系,教授北京市100083 [2]北京科技大学 [3]北京科技大学新金属材料国家重点实验室

出　　处：《材料研究学报》2003年第5期520-529,共10页Chinese Journal of Materials Research

基　　金：国家重点基础研究No.1998061506;教育部高等学校骨干教师资助计划资助项目

摘　　要：利用背散射电子衍射取向成像技术定量分析了热模拟单向压缩条件下Q235碳素钢热变形时铁素体的织构形成规律。结果表明,在710℃纯铁素体热压缩过程中,形成〈100〉和〈111〉方向的线织构。〈111〉方向织构增强的速度较快,到应变为1.0时达最大值,然后随应变的加大而减弱;〈100〉方向织构在形变量较小时增强的速度较慢,在大应变时增强的速度很快。大应变时虽导致一定程度的动态再结晶,使铁素体晶粒细化,但组织不均匀,织构过强,造成强烈的各向异性。在奥氏体与铁素体两相区变形时,先共析铁素体因形变同样产生强烈的织构。随着形变温度的提高和先共析铁素体的减少,织构减弱。The texture evolution of ferrite during warm compression of Q235 low carbon steel was determined quantitatively by means of orientation mapping based on the EBSD technique. Results show that the and fiber textures developed at different rates during warm compression at 710°C. The texture formed quickly as strain increased and after the arrival of its maximum at the strain of 1 it descended. By contrast, the texture evolved slowly at low strain and increased quickly at heavy strain. Although ferrite recrystallized dynamically to some extent at high strain rate, a non-uniform microstructure was got together with a strong texture leading to a pronounced anisotropy. The deformation in the two-phase region of α-γ led to preferred orientations in deformed pro-eutectoid ferrite with respect to the less deformed, strain-induced ferrite. The increase of deformation temperature reduced the texture intensity.

关 键 词：金属材料 材料的组织 取向成像 织构 低碳钢 热变形 

分 类 号：TG113[金属学及工艺—物理冶金]