激光扫描速度对304不锈钢薄板组织和性能的影响  

Influence of Laser Scanning Speed on Microstructure and Properties of 304 Stainless Steel Sheet

作　　者：郭国林[1,2] 戴国洪 周自强 徐正亚[1,2] 

机构地区：[1]常熟理工学院机械工程学院,江苏常熟215500 [2]江苏省机电产品循环利用技术重点实验室,江苏常熟215500

出　　处：《机械设计与制造》2018年第3期195-197,共3页Machinery Design & Manufacture

基　　金：江苏省科技支撑计划项目(BE2011096);苏州市科技计划项目(SGZ2013125);江苏省机电产品循环利用技术重点实验室开放基金资助项目(KY301201402-2)

摘　　要：研究了在5k W激光功率下,激光扫描速度对304不锈钢薄板搭接接头组织和性能的影响。实验结果表明,焊缝区出现分层现象,层界存在着向两侧层中心延伸的树枝晶组织,层中心为细小的等轴晶。熔合线附近为树枝晶组织,垂直于熔合线向焊缝中心生长。不同扫描速度下,焊缝区的硬度均低于母材硬度,随着扫描速度的提高,焊缝区的硬度值趋于稳定,焊缝中心的硬度值,呈现下降趋势。扫描速度不同,焊接接头强度也不同,扫描速度为72mm/min时,焊接接头的抗拉强度接近于母材的强度。The influence of laser scanning speed on microstructure and properties of lap joints of 304 stainless steel sheet was investigated,when laser power was 5 k W. The test results show that multilayer molten metal is found in the weld seam,and layer boundary is dendrite extending to the center of both sides,layer center is fine equiaxed grains. Near the fusion line is dendrite,perpendicular to the fusion line to the weld center. The hardness of the weld seam is lower than that of the base metal at different scanning speeds. The hardness value of the weld seam tends to be stable and the hardness value of the weld center is decreased with the increase of the scanning speed. The strength of the welded joints is different because of the differences of scanning speeds. The tensile strength of the welded joints is close to that of the base metal when the scanning speed is 72 mm/min.

关 键 词：扫描速度 304不锈钢薄板 显微组织 硬度 抗拉强度 

分 类 号：TH16[机械工程—机械制造及自动化] TG456.7[金属学及工艺—焊接]