Structure Design Of Laser Selective Melting Rapid Prototyping Equipment

Selective laser melting technology, which is one of the most promising addictive manufacturing technologies, has been widely used for industrially manufacturing metal parts as its products have good performance and can be used without another working procedure.Besides,the research of manufacturing process for new SLM materials must be one of its most important directions. In order to meet the experimental needs of exploring the new forming method for new materials,this thesis focus on the research of system design of SLM equipment for ceramics, composite materials and other new materials based on the experiences of operating the SLM equipment and manufacturing metal parts.Based on the working principles and key device movement, the overall design of SLM experimental equipment is proposed, in which the equipment is divided into four systems:the control system, powder-coating systems, laser scanning system and atmosphere protection system. After the overall design of each subsystem, it focuses on the need functions and accuracy of the control system.As the commerical SLM equipments are not suitable for experimental research for their powders supplement unit of over-complex structure and powder wastage.this paper propose the design of powders supplement unit based on hopper and dusting drum which can make the equipment have compacter structure and high usage of powders.In order to get powder layer with higher density,the design of powder coating device with a roller as its fuctional unit instead of coating blade is put forward.For its analysis, first establish the mechanical model and motion model of the interaction between the powders and roller, thus to determine the parameters of the structure design which will affect the effect of powder-coating. Then proceed to dynamics simulation analysis of the powder-coating device, and back to guide design based on the model simulation results.Focus-adjustment equipment can make the laser focus plane have a moving distance of 1 Omm so as to have more possibility for new research. After the design complete in guidance of its function, the model of focus-adjustment equipment is simulated in ANSYS to verify its stability. To make sure the working atmosphere of SLM manufactue, atmosphere protection system is designed to meet the needs of deoxidization and dust removal. Based on the flow field simulation analysis of initial program, some design iterations are produced.Finally, by the incomplete equipment with absence of atmosphere protection system, series of technology experiments are conducted to compare the effects of different powder-coating device and to analyze the effects of laser power and layer thickness on the forming quality of ceramic in order to verify the rationality of the system design.