能量密度对高氮不锈钢选区激光熔化成形质量的影响  

Effect of Energy Density on Selective Laser Melting Quality of High Nitrogen Stainless Steel

作　　者：崔小杰 王亚超 任建彪 孙鑫 赵定国 王书桓 CUI Xiaojie;WANG Yachao;REN Jianbiao;SUN Xin;ZHAO Dingguo;WANG Shuhuan(College of Metallurgy and Energy,North China University of Science and Technology,Tangshan 063210,China)

机构地区：[1]华北理工大学冶金与能源学院,河北唐山063210

出　　处：《热加工工艺》2024年第1期23-28,共6页Hot Working Technology

基　　金：国家自然科学基金项目(51774139,52074128);河北省自然科学基金项目(E2020209014);河北省自然科学基金重点资助项目(E2019209597)。

摘　　要：固定扫描层厚0.02 mm,扫描间隔0.11 mm,采用不同激光功率(100~300 W)、扫描速度(200~1000 mm/s)进行了高氮不锈钢的选区激光熔化成形试验,研究了能量密度对选区激光熔化成形质量的影响。结果表明,在低扫描速度(200 mm/s)下,试样的相对致密度与激光功率成反比;在高激光功率(300 W)下,相对致密度与扫描速度成正比;在45.45~681.82 J/mm^(3)区间,随激光能量密度的增加相对致密度呈先上升后下降的趋势,在136.36~443.18 J/mm^(3)区间,随激光能量密度的增加显微硬度减小,当能量密度为136.36 J/mm^(3)时,试样相对致密度最佳,为98.85%,显微硬度最高,为409 HV0.3。各工艺参数下的试样内部未出现大尺寸裂纹缺陷,内部缺陷主要是未熔粉体、微气孔及球化颗粒;在200 W激光功率下,试样内部缺陷数量及种类随着扫描速度的降低而增大;在1000 mm/s扫描速度下,试样内部缺陷数量及种类随激光功率增大而减小。Under the scanning layer thickness of 0.02 mm,scanning spacing of 0.11 mm,the selective laser melting tests of high nitrogen stainless steel was carried out at different laser power of 100-300 W and scanning speed of 200-1000 mm/s.And the effect of process parameters on the selective laser melting quality of the high nitrogen stainless steel was studied.The results show that under the low scanning speed of 200 mm/s,the relative density of the sample is inversely proportional to the laser power,and under the high laser power of 300 W,the relative density of the sample is proportional to the scanning speed.In the range of 45.45-681.82 J/mm^(3),the relative density increases first and then decreases with the increase of laser energy density.In the range of 136.36-443.18 J/mm^(3),the microhardness decreases with the increase of laser energy density.When the energy density is 136.36 J/mm 3,the relative density of the sample is the best of 98.85%,and the microhardness is the highest of 409 HV0.3.There are no large-scale crack defects in the sample under various parameters.The internal defects are mainly unfused powder,micro pores,and balling particles.Under the laser power of 200 W,the number and type of internal defects in the sample increase with the decrease of scanning speed.Under the scanning speed of 1000 mm/s,the number and type of internal defects in the sample decrease with the increase of laser power.

关 键 词：选区激光熔化 高氮不锈钢 相对致密度 显微硬度 

分 类 号：TG456.7[金属学及工艺—焊接]