低碳钢过冷奥氏体形变过程超细铁素体的形成  

ULTRA-FINE FERRITE FORMATION DURING DEFORMATION OF UNDERCOOLED AUSTENITE IN A LOW CARBON STEEL

作　　者：齐俊杰[1] 杨王玥[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：《金属学报》2002年第9期897-902,共6页Acta Metallurgica Sinica

基　　金：国家重点基础研究发展规划资助项目 G1998061506

摘　　要：采用过冷奥氏体在A3-Ar3之间变形工艺,获得平均晶粒尺寸约为 2μm的微细铁素体晶粒组织.过冷奥氏体形变过程的组织演变包括两个阶段:形变前期以形变强化相变铁素体转变为主导;当相变基本完成后,形变后期以铁素体的动态再结晶为主.形变强化相变是一以形核为主的过程,是晶粒细化的主要原因.应变量较小时,铁素体主要沿原奥氏体晶界及晶内变形带等位置形核,随应变量的增加,以铁素体转变前沿畸变区的反复形核为主.Based on the theory of deformation enhanced transformation, ultra-fine ferrite structure with grain size of about 2 mum was formed during deformation of undercooled austenite between A(3)-Ar-3. Two mechanisms are involved during the deformation process: deformation-enhanced transformation is the dominated factor in the early stage of deformation, while ferrite dynamic recrystallization plays a major role in the final stage after deformation enhanced austenite to ferrite transformation nearly completed. Deformation enhanced transformation is. a nuleation dominated process, which is the main mechanism of grain refinement. Ferrite grains nucleate at austenite grain boundary and, areas with high density defect under small strain, then form repeatedly at areas with high stored energy in front of the ferrite/austenite interface.

关 键 词：过冷奥氏体 低碳钢 形变强化相变 铁素体动态再结晶 晶粒细化 

分 类 号：TG142.31[一般工业技术—材料科学与工程]