激光选区熔化成形工艺对304L不锈钢冲击韧性的影响  

Effect of Selective Laser Melting Process on Impact Toughness of 304L Stainless Steel

作　　者：李艳丽[1,4] 吴代建 陈诚[2] 门正兴 张宏[3,4,5] LI Yan-li;WU Dai-jian;CHEN Cheng;MEN Zheng-xing;ZHANG Hong(Department of Materials Engineering,Sichuan Engineering Technical College,Sichuan Deyang 618000,China;School of Aeronautical Manufacturing Industy,Chengdu Aeronautic Polytechnic,Chengdu 610021,China;a.College of Architecture and Environment b.Failure Mechanics and Engineering Disaster Prevention and Mitigation Key Laboratory of SichuanProvince,Sichuan University,Chengdu 610065,China;National Engineering Research Center for advanced manufacturingtechnology and equipment of large castings and forgings,Chengdu 610021,China)

机构地区：[1]四川工程职业技术学院材料工程系,四川德阳618000 [2]成都航空职业技术学院航空装备制造产业学院,成都610021 [3]四川大学建筑与环境学院,成都610065 [4]四川大学破坏力学与工程防灾减灾四川省重点实验室,成都610065 [5]大型铸锻件先进制造技术与装备国家工程研究中心,成都610021

出　　处：《精密成形工程》2022年第10期126-132,共7页Journal of Netshape Forming Engineering

基　　金：四川省科技计划重点研发项目(2020YFG0204);中国博士后基金(2019M653396);四川大学-自贡政府战略合作支持项目(2019CDZG-4);四川大学-宜宾政府战略合作支持项目(2019CDYB-24);四川大学博士后基金(2019SCU12056)。

摘　　要：目的了解激光选区熔化(SLM)成形工艺参数对304L不锈钢冲击韧性的影响,从而得到304L不锈钢的最佳成形工艺参数。方法对激光功率300~340 W,激光扫描速度800~1500 mm·s^(‒1)条件下的激光选区熔化成形304L不锈钢开展冲击试验,通过表面硬度、微观组织及断口形貌观察对冲击韧性的影响规律进行分析。结果SLM成形304L不锈钢微观组织为跨越熔池生长形成的不规则柱状晶粒,成形工艺参数对试样表面硬度影响不显著;随着激光功率的增大和激光扫描速度的降低,304L不锈钢断面致密程度提高,孔洞类缺陷尺寸减少且数量减少,冲击韧性增大,冲击功最大值为141.9 J。结论基于冲击试验结果,在激光体能量密度为100~140 J/mm3的条件下,304L冲击韧性稳定在138 J左右,为SLM成形304L材料的最佳成形参数区间。The work aims to obtain the optimum process parameters of 304L stainless steel,the influence of process parame-ters on impact toughness of 304L stainless steel by selective laser melting(SLM)were studied.Impact tests were carried out on 304L stainless steel formed by selective laser melting under laser power of 300-340 W and laser scanning speed of 800-1500 mm/s,the regular pattern of process parameters on impact toughness were analyzed through the surface hardness,microstructure and transverse fracture morphology.The results show that the microstructure of 304L stainless steel formed by SLM is irregular columnar grains grown across the molten pool,and the forming process parameters have no significant effect on the surface hard-ness of the sample.With the increase of laser power and the decrease of laser scanning speed,the densification degree of 304L stainless steel section is improved,the size and number of hole defects are reduced,the impact toughness is increased,and the maximum impact energy is 141.9 J.Based on the impact test results,the impact toughness value of 304L is stable at about 138 J,when the laser volume energy density is within 100-140 J/mm3,which is the optimum process parameter range to prepare 304L stainless steel.

关 键 词：激光选区熔化 304L 冲击韧性 工艺参数 

分 类 号：TG316[金属学及工艺—金属压力加工]