扫描速度对CuCr合金激光表面快速熔凝改性层性能的影响  

Effect of Scanning Speed on Properties of Laser Surface Remelting Layer of CuCr Alloy

作　　者：王旭[1,3] 虞钢 何秀丽[1,3] 李少霞 田崇鑫[1,3] 邵佳昀 刘宝华[4] Wang Xu;Yu Gang;He Xiuli;Li Shaoxia;Tian Chongxin;Shao Jiayun;Liu Baohua(Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China;Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China;School of Engineering Science,University of Chinese Academy of Sciences,Beijing 100049,China;Beijing Orient Vacuum Electric Co.,Ltd.,Beijing 101500,China)

机构地区：[1]中国科学院力学研究所,北京100190 [2]中国科学院大学材料与光电研究中心,北京100049 [3]中国科学院大学工程科学学院,北京100049 [4]北京京东方真空电器有限责任公司,北京101500

出　　处：《激光与光电子学进展》2022年第1期233-239,共7页Laser & Optoelectronics Progress

基　　金：国家自然科学基金(11672304,11502269);北京市科技计划项目(Z181100003818015)。

摘　　要：利用高功率密度激光开展CuCr50合金表面快速熔凝改性实验,研究扫描速度对材料熔凝改性层深度、显微硬度、表面粗糙度以及拉伸和断裂特性的影响。结果表明:随着扫描速度由2000 mm/min增加到8000 mm/min,熔凝层平均深度从(486.2±32.8)μm降至(26.8±13.4)μm,平均硬度值由203 HV提升到250 HV,较基体硬度(85 HV)提升了约3倍;表面粗糙度随着扫描速度的降低而增大;单侧表面激光熔凝处理后材料的屈服强度较未处理材料提升了16.5%~28.0%,基体断裂主要是以沿晶界扩展的沿晶断裂,熔凝层断口呈现出等轴韧窝状的断裂特征。表面改性后CuCr50合金的硬度和强度均有大幅提升,通过改变扫描速度可以获得综合性能较好的激光表面改性效果。The effects of scanning speed on the remelting layer depth,microhardness,surface roughness,and tensile and fracture behaviors of high energy density laser surface remelting CuCr50 alloy were investigated.The results show that with the increase of scanning speed from 2000 mm/min to 8000 mm/min,the average depth of remelting layer decreases from(486.2±32.8)μm to(26.8±13.4)μm and the average microhardness increases from203 HV to 250 HV,which is about three times of the substrate microhardness(85 HV).The surface roughness increases with the decrease of scanning speed.The yield strength of CuCr50 alloy after laser remelting treatment on one side surface is 16.5%-28.0% higher than that of untreated alloy.The fracture morphology of the remelting layer is equiaxed dimple,showing the ductile fracture.The fracture morphology of the substrate is mainly intergranular fracture extending along the grain boundary,showing the brittle facture.Thus,mechanical properties including microhardness and yield strength of the modified CuCr50 alloy are greatly improved.By modulating the scanning speed,laser surface modified alloy with better comprehensive performance can be obtained.

关 键 词：激光技术 表面改性 扫描速度 CUCR合金 显微组织 力学性能 

分 类 号：TN249[电子电信—物理电子学]