摘要
采用常用42CrMo钢为研究材料,探索激光冲击预处理对离子渗氮的催渗效果与作用机理,提升离子渗氮效率。采用光学显微镜、粗糙度仪、扫描电镜、维氏显微硬度计研究激光冲击及离子渗氮后表层特性。结果表明,激光冲击对于离子渗氮具有显著的催渗效果。相同离子渗氮条件下,化合物层厚度和有效扩散层厚度都提高到传统离子渗氮的2倍左右。同时激光冲击预处理可显著提高试样表面硬度,并平缓截面硬度的下降趋势。激光冲击预处理对离子渗氮产生的显著作用源于:激光冲击预处理使试样表面粗糙度从0.015μm提高到0.454μm,有利于N原子吸附和氮化物形成;表层形成了厚度约200μm的变形层,为N原子提供扩散通道,有利于提高扩散层氮浓度。
42CrMo steel was used in this research,and the effect and mechanism of laser shock peening(LSP) pretreatment on plasma nitriding were primarily investigated.The aim was to obtain a novel rapid plasma nitriding technology.Optical microscope,surface roughness tester,scanning electron microscope and Vickers micro-hardness tester were used to observe and evaluate the surface characteristics.Results show that laser shock peening has obvious catalysis effect on plasma nitriding.The thickness of the compound layer and effective diffusion layer can be effectively enhanced by laser shock peening under the same plasma nitriding condition,which is about twice thicker than that of the conventional plasma nitriding.Meanwhile,LSP pretreatment can significantly improve the surface hardness and slow down the decreasing trend of cross-sectional hardness.The significant effect of LSP pretreatment on plasma nitriding is that LSP pretreatment increases the surface roughness of the sample from 0.015 to 0.454 μm,which is beneficial to the adsorption of N atoms and the formation of nitrogen compounds.Additionally,a deformation layer(about 200 μm) was formed by LSP pretreatment on the surface,providing a diffusion channel for N atoms,which is beneficial to the increase of nitrogen concentration in the diffusion layer.
作者
唐磊
贾蔚菊
孙斐
胡静
TANG Lei;JIA Weiju;SUN Fei;HU Jing(Jiangsu Key Laboratory of Materials Surface Science and Technology,Changzhou University,Changzhou 213164,China;Northwest Institute for Non-ferrous Metal Research,Xi'an 710016,China;Department of Mechanical Engineering,Changzhou Institute of Light Industry Technology,Changzhou 213164,China)
出处
《中国表面工程》
EI
CAS
CSCD
北大核心
2018年第6期9-13,共5页
China Surface Engineering
基金
国家自然科学基金(51774052)
江苏省第三期优势学科建设项目(PAPD-3)
江苏高校品牌专业建设工程资助(TAPP)~~
关键词
激光冲击
离子渗氮
预处理
渗氮效率
laser shock peening
plasma nitriding (PN)
pre-treatment
nitriding efficiency
