摘要
采用选区激光熔化技术(Selective laser melting,SLM),在55Mn2钢表面成形Inconel718涂层。系统研究不同激光线能量密度(η)对涂层表面组织形貌、相对致密度、显微硬度及涂层基体间剪切结合强度的影响。结果表明:随着激光线能量密度的提高,涂层表面因液体球化现象产生的球形颗粒减少,内部析出的δ相逐渐细化、柱状晶均匀分布。涂层内部结构致密度和显微硬度随着激光线能量密度的提高而逐渐增加,当线能量密度为357.14 J/m时,致密度达到99.6%,显微硬度达到428.6HV 0.2。由剪切断口形貌可知涂层与基体间为韧性断裂机制,涂层与基体间的抗剪切强度在实验参数范围内为基体的1.9~2.15倍。本研究对采用激光选区熔化技术修复和强化轧辊表面提供了实验及理论依据。
The Inconel718 coating was formed on 55Mn2 steel by selective laser melting(SLM).The effects of laser line energy density on the surface microstructure,relative density,microhardness of coating and shear strength between the coating and the substrate were systematically studied.The results showed that with the increase of laser line energy density,the number of spherical particles on the surface of the coating decreased due to nodulizing phenomenon.The internal precipitatedδphase refined gradually and the columnar crystal evenly distributed.The internal structure density and microhardness of the coating increased gradually with the increase of the laser line energy density.The density and the microhardness reached 99.6%and 428.6HV 0.2 when the line energy density was 357.14 J/m.The fracture morphology of the coating and the matrix displayed a ductile fracture mode,and the shear strength in the experimental parameter range was 1.9 to 2.15 times of the matrix.The results provide an experimental and theoretical basis on repairing and strengthening the roll surface by selective laser melting.
作者
秦翔
杨军
邹德宁
谢燕翔
QIN Xiang;YANG Jun;ZOU Dening;XIE Yanxiang(School of Metallurgical Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China;Shaanxi Key Laboratory of Gold and Resources,Xi’an University of Architecture and Technology,Xi’an 710055,China;Shaanxi Key Laboratory of Surface Engineering and Remanufacturing,Xi’an University,Xi’an 710065,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2020年第4期93-97,共5页
Materials Reports
基金
国家自然科学基金(51774226
U1460104)~~
关键词
选区激光熔化
组织形貌
显微硬度
剪切强度
selective laser melting
microstructure
microhardness
shear strength
