Q235碳素钢超细铁素体在奥氏体内的形核  

Nucleation of Ultra-fine Ferrite in Austenite of A Q235 Low Carbon Steel

作　　者：杨平[1] 张栋华[1] 孙祖庆[2] 

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

出　　处：《北京科技大学学报》2002年第2期211-215,共5页Journal of University of Science and Technology Beijing

基　　金：国家重点基础研究课题"新一代钢铁砂料的重大基础研究"(973)(No.G1998061506);国家教育部‘高等学校骨干教师资

摘　　要：利用扫描电镜观察了 Ｑ２３５碳素钢形变强化相变过程中超细铁素体在奥氏体内部的 形核；使用背散射电子衍射（ＥＢＳＤ）技术分析了析出的铁素体取向．结果表明，随内、外界条件 不同，奥氏体内有两类典型的铁素体形核地点：形变带及奥氏体晶界附近的形变不均匀区 原 始奥氏体晶粒尺寸的增加，形变温度的降低有利于铁素体的形变带形核．在Ａ３－Ａｒ３的超细铁素 体最佳形成温度区间，靠近Ａ３形变可使铁素体及第２组织均匀分布．形变带形核造成带状分布 的铁素体及第２相，不仅形貌上出现方向性，铁素体取向也出现择优．The nucleation of ultra-fine ferrite inside austenite was followed during deformation-enh- anced transformation in a Q235 low carbon steel. EBSD technique was applied to reveal the orientation fea- tures of ferrite formed at different places. Results indicate that there are two typical nucleation sites inside aus- tenite, namely, deformation bands and deformation inhomogeneities near austenite grain boundaries. Increas- ing austenite grain size and decreasing deformation temperature favor to the ferrite formation at deformation bands. In the suitable deformation temperatures of A3-Ar3 for ultra-fine ferrite, the deformation near A, leads to a uniform distribution of ferrite as well as second phases. The band-like ferrite and second phases caused by the nucleation at deformation bands gives rise to not only the anisotropy in microstructure but also in ferrite orientation.

关 键 词：Q235碳素钢 超细铁素体 奥氏体 形核 形变强化相变 EBSD 

分 类 号：TG142.31[一般工业技术—材料科学与工程] TG142.11[金属学及工艺—金属材料]