钢激光加热组织遗传性的研究  

A STUDY ON THE STRUCTURAL INHERITANCE OF THE STEEL HEATED BY LASER

作　　者：安世民[1] 姚远 

机构地区：[1]大连理工大学 [2]长春汽车材料研究所

出　　处：《金属热处理学报》1990年第2期9-18,共10页

摘　　要：本文研究了42CrMo钢非平衡组织在激光加热过程中出现的组织遗传现象。利用激光加热层组织对应不同的加热温度这一有利条件,研究了激光加热时奥氏体的形成过程。用光学显微镜和薄膜透射电镜研究了基体组织和激光加热层组织的变化情况;用复型透射电镜观察了激光加热两相区奥氏体的形核长大过程。结果得出:激光加热奥氏体有有序和无序两种形成方式。对淬火组织和回火组织,有序γ以无扩散逆转变方式呈针状(γ_α~′)形核;与已有工作不同,其形核温度比无序扩散形核的γ_g高;有序转变的γ使组织出现遗传,而无序转变的γ则削弱组织遗传;原始组织和激光加热参数通过影响γ形成方式影响组织遗传性。The structural inheritance phenomena occured in nonequilibrium structureof 42CrMo obtained by laser heating were studied.Since the structures in thelaser heating zone can be related to definite heating temperatures,the forma-tion of γ phase during laser heating was explored.The structures and mechanism of transformation in the specimen were inve-stigated extensively by means of optical microscopy,transmission electronmicroscopy.The results show that the ordered and disordered formation of γ phase are bo-th appeared in laser heating.For quenched and quench-tempered specimen thenucleation of ordered γ phase is formed to proceed as non-diffusion-type tran-sformation,and resulted in acicular crystals(γa).It has been establishedalso that the nucleation temperature of such γ phase is higher than that ofthe diffusion-controlled disordered γ phase,rather than lower,stated in pre-vious works.Ordered transformation of γ develops structural inheritance,where-as disordered transformation has a weakening effect on the structural in-heritance.Original structure of steel and laser processing parameters all effectthe structural inheritance by their influences on the formation of γ phaseduring heating.

关 键 词：钢 组织遗传性 激光加热 奥氏体 

分 类 号：TG142.1[一般工业技术—材料科学与工程]