Surface Nanocrystallization of C45E4 Steel by Ultrafast Electropulsing-ultrasonic Surface Treatment

作     者：陈龙 WANG Haibo LIU Dan YE Xiaoxin 唐国翌 

作者机构：School of Materials Science and Engineering Tsinghua University Beijing 100084 China Advanced Materials Institute GraduateSchool at Shenzhen Tsinghua University Shenzhen 518055 China Key Laboratory for Advanced Materials of Ministry of Education Department of Materials Science and Engineering Tsinghua University Beijing 100084 China 

出 版 物：《Journal of Wuhan University of Technology(Materials Science)》 (武汉理工大学学报（材料科学英文版）)

年 卷 期：2017年第32卷第6期

页      面：1426-1432页

核心收录：

学科分类：08[工学] 0802[工学-机械工程] 080201[工学-机械制造及其自动化] 

基　　金：Funded by the Natural Science Foundation of China(No.50571048) the Research & Development Funding Project of Shenzhen(No.JCYJ20120619152539900) 

主　　题：electropulsing-ultrasonic surface treatment surface nanocrystallization refinedmicrostructure microhardness 

摘      要：The effect of high-energy electropulsing-ultrasonic surface treatment（EUST） on the surface properties and the microstructure evolution of C45 E4 steel was investigated. Refined microstructure and reduced surface roughness were obtained owing to the surface nanocrystallization process. Compared with the ultrasonic surface treatment（UST）, the impact depth of the surface strengthened layer was increased by 40% to 700 μm after EUST. The average grain size of the surface nanocrystallization layer was reduced to 30-50 nm. The surface roughness of the C45 E4 steel was reduced to 0.25 μm, and the surface microhardness was dramatically enhanced to 460 HV. The improvement of microstructure and micro-hardness at ambient temperature was likely attributed to the acceleration of atomic diffusion and the enhancement of plastic deformation ability in the surface strengthened layer under the influence of electropulsing. Due to the electropulsing-assisted ultrasonic strengthening effect, the surface nanocrystallization in this ultrafast procedure was noticeably enhanced.