钢中贝氏体相变机制的研究  

RESEARCH ON BAINITE TRANSFORMATION IN STEELS

作　　者：方鸿生[1] 杨志刚[1] 杨金波[1] 白秉哲[1] 

机构地区：[1]清华大学材料科学与工程系,北京100084

出　　处：《金属学报》2005年第5期449-457,共9页Acta Metallurgica Sinica

基　　金：高等学校博士学科点专项科研基金资助项目20020003084

摘　　要：简要地总结了国内近年来在贝氏体相变理论研究方面的主要成果,包括以下方面: (1)发现钢中的贝氏体超精细结构; (2)贝氏体表面浮突完全由贝氏体铁素体长大过程中形变产生,单一超亚单元对应的浮突呈帐篷型;(3)贝氏体铁素体宽面上存在三维巨型台阶,在近N-W关系下相变单元宽面接近(335)f,为扩散型界面; (4)发现钢中贝氏体碳化物在α/γ界面的γ侧形核并向奥氏体内生长; (5)建立了贝氏体激发形核-台阶长大模型,理论计算表明这种机制是合理的,它成功地解释了贝氏体的多层次复杂结构,以及上贝氏体、下贝氏体等不同形态的形成原因等.The main research results about the mechanism of bainite formation are described as follows: (1) Bainite in steel is of ultra-fine structure; (2) Surface relief of bainite is produced only by the deformation of the growing bainitic ferrite; furthermore, surface relief of a single smallest structural unit is tent-shaped rather than invariant-plane-strain-typed; (3) 3-dimensional superledges appear on the broad face of bainite ferrite and the austenite (335) plane of the structural units of bainitic sheaves is reasoned to be a diffusional interface, which indicates the growth of lower bainite by a diffusion process; (4) The bainite carbide nucleates in the gamma side of alpha/gamma interface and grows toward austenite; (5) Sympathetic nucleation-ledgewise growth model of bainite suggested on the base of the experiment data was proved by theoretical calculation.

关 键 词：贝氏体相变 精细结构 表面浮突 激发形核-台阶长大机制 

分 类 号：TG111.5[金属学及工艺—物理冶金] TG142[金属学及工艺—金属学]