SLM实时预熔/重熔的新型成型工艺研究  

Research on a New SLM Process of Pre-melting and Re-melting

作　　者：刘志远[1] 钱波[1] 李培 张剑睿 池敏 李腾飞[1] Liu Zhiyuan;Qian Bo;Li Pei;Zhang Jianrui;Chi Min;Li Tengfei(School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai, 200237 China)

机构地区：[1]华东理工大学机械与动力工程学院,上海200237

出　　处：《机械科学与技术》2019年第4期566-570,共5页Mechanical Science and Technology for Aerospace Engineering

基　　金：国家自然科学基金项目(21206152)资助

摘　　要：SLM(Selective laser melting)工艺是增材制造领域发展较为迅猛的一种工艺,其在复杂金属结构零件的制造领域具有极大的优势。为了降低SLM工艺的孔隙率,获得更高的致密度,以及更好的机械性能(硬度),提出了一种新型工艺,先对粉末层进行低激光功率的预熔处理,然后使用高功率的激光再次熔化,实现逐层重熔。8组对比试验结果表明:与只经过单熔处理的零件相比,经过预熔与重熔两次熔化后的零件,孔隙率从0.186%减少到0.039%,硬度从237.5 HV提高到264.3 HV,组织均匀性提高,组织呈马氏体结构。由此说明,SLM实时预熔重熔成型工艺在复杂金属结构零件的制造领域,具有较好的应用前景。Selective laser melting (SLM) is an attractive manufacturing technique for producing metal parts with complex geometries and high performance. The powder materials used in this study was 316L stainless steel powder. In order to reduce porosity, obtain higher density and better mechanical properties (hardness), a new process was proposed. The powders were pre-melted by using the low laser power, then the powders were melted again by using the high power laser to realize the re-melting process layer by layer. The results show that the porosity decreases from 0.186% to 0.039%, and the hardness value increases from 237.5 HV to 264.3 HV after pre-melting and re-melting. The homogeneity of martensite is improved . It shows the new process had a great prospect for manufacturing the complex metal parts.

关 键 词：预熔 重熔 孔隙率 微观结构 硬度 

分 类 号：TH825[机械工程—仪器科学与技术] O329[机械工程—精密仪器及机械]