35CrMo钢表面扫描电子束铬镍合金化组织和硬度的研究  

Study on Microstructure and Hardness of Scanning Electron Beam Chromium-nickel Alloying on 35CrMo Steel Surface

作　　者：魏德强[1] 吕少鹏 张学静[1] 王荣[1] WEI Deqiang;LYU Shaopeng;ZHANG Xuejing;WANG Rong(Faculty of Mechanical and Electrical Engineering,Guilin University of Electronic Technology,Guilin 541004,China)

机构地区：[1]桂林电子科技大学机电工程学院,广西桂林541004

出　　处：《热加工工艺》2020年第14期102-106,共5页Hot Working Technology

基　　金：国家自然科学基金项目(51665009);广西自然科学基金重点项目(2017GXNSFDA198007)。

摘　　要：为改善35CrMo钢的表面性能,采用电子束扫描与等离子热喷涂相结合的方法在其表面进行铬镍合金化处理;探究了强化层组织形貌和硬度的分布规律及电子束扫描工艺参数对强化层显微组织及硬度的影响规律。结果表明:35CrMo钢经合金化处理后,表面由合金化区、热影响区和基体三部分组成,合金化区显微组织为短柱或近似等轴晶粒,热影响区为针状马氏体,基体为珠光体和屈式体。铬镍元素在合金层发生固溶扩散,并析出弥散的Cr23C6增强相。合金层显微硬度随束流的增大先增大后减小,随移动速度的增大而减小,热影响区硬度随束流增大先增大后减小,随移动速度减小先增大后减小。In order to improve the surface properties of 35CrMo steel, chromium-nickel alloying was carried out on the surface of 35CrMo steel by the combination of electron beam scanning and plasma thermal spraying. The distribution of microstructure and hardness of the strengthening layer and the influence of the process parameters of electron beam scanning on the microstructure and hardness of the strengthening layer were investigated. The results show that the surface of 35CrMo steel after alloying consists of alloying zone, heat affected zone and substrate. The microstructures of the alloying zone are short columns or nearly equiaxed grains, the heat affected zone is acicular martensite, and the substrate is pearlite and refractive. The solid solution diffusion of chromium and nickel occurs in the alloy layer, and the dispersed Cr23C6 reinforcement phase is precipitated. The microhardness of the alloy layer increases first and then decreases with the increase of beam current, and decreases with the increase of moving speed. The hardness of heat affected zone increases first and then decreases with the increase of beam current, and increases first and then decreases with the decrease of moving velocity.

关 键 词：电子束扫描 合金化 35CRMO钢 显微硬度 显微组织 

分 类 号：TG174.4[金属学及工艺—金属表面处理]