Mingyue Shen is a PhD researcher working on the post-treatment of selective laser melted parts. She completed her master’s degree on the microstructure and mechanical properties of laser additive manufactured TiC reinforced Inconel 625 composites in the School of Materials and Engineering at Beihang University in 2017. Her undergraduate degree was in the area of materials physics from Yanshan University. Her main research interests are in the areas of polishing internal structures and laser additive manufacturing.
Research Interests (Lay Summary)
Mingyue Shen is working on the polishing of internal structures on selective laser melted parts. Products with internal structures such as conformal channels and lattice structures are widely used in automotive, aerospace, medical and moulding industries. Compared with traditional manufacturing technologies, selective laser melting (SLM) is more attractive because of its high accuracy and lack of geometrical limitations in preparing parts with complex internal structures.
Although SLM has a lot of attractive advantages, it still faces an apparent limitation in terms of poor surface quality. Surface finish is an important factor in the application of a part since it influences multiple functional characteristics, such as biological response, mechanical properties, fluid dynamics, and heat transfer. However, the surface quality of a part produced by SLM is usually inferior because of various factors such as balling effects and staircase effects during laser processing. Nowadays, post treatment methods such as milling are widely used for quality improvement of outer surfaces in SLM.
The existing polishing tools are limited in functionality and it is difficult to achieve effective surface improvement for SLM parts with internal structures. Thus, research on surface finish of internal structures on SLM parts is required. The objective of Mingyue’s research is to develop an effective polishing process for the surface finish of internal structures on SLM parts.
Polishing is a potential post-treatment method to decrease surface roughness of internal structures on SLM parts. The optimisation and flexible control of polishing processes can improve the efficiency of post treatment and benefit the overall SLM production process and cost.
Mingyue’s research is examining the material removal mechanism of SLM parts through polishing and will lead to an optimised polishing process. By developing an improved polishing methodology for decreasing the surface roughness of internal structures, a wider application space for AM components can be realised.
Materials investigated will include 316L stainless steel, CoCr alloy and Ti6Al4V. Surface finishing examinations will include electrochemical polishing and abrasive flow machining. The research will evaluate the effect of polishing on the surface roughness and material properties and a hybrid polishing process which combines electrochemical polishing and abrasive flow machining will be developed for SLM parts with internal structures.