Study On The Process Parameters Of Selective Laser Melting

Selective Laser Melting(SLM)technology is a kind of technology that uses metal powder to melt completely and solidifies under the heat of laser beam.SLM technology can be used to produce complex structural metal parts with high precision and high density,which is widely used in aerospace,biomedical field and so on.However,SLM technology is still in its infancy,and the research on forming quality of metal processing parts is still in progress.Based on the research of the influence of SLM process parameter on the forming quality of processing parts,this paper puts forward specific optimization methods from scanning strategy and curing process parameters.In the aspect of scanning strategy,we analyze and compare the advantages and disadvantages of four filling algorithms,which are scan line filling,bias filling,partition scanning line filling and helix filling,so as to design a contour offset scan line filling algorithm.The contour offset scan line filling algorithm solves the problem of the poor quality of the contour boundary formation caused by the overlap between the intersection line and the contour line.This paper also introduces the scan line filling algorithm of arbitrary angle.On the basis of the inclination filling method of arbitrary scanning line,an interlayer scanning strategy for rotation fixed scanning angle of each layer is introduced.In this paper,an infrared thermometer temperature measuring system has been built.By monitoring the temperature of the workpiece surface,we have designed an experiment to monitor the temperature distribution in the forming process of different area workpiece.Under the same processing conditions,the temperature change rate of the small size workpiece is very large when the parts with large difference of the workpiece are large,which is very easy to cause the poor forming quality of the small workpiece.In the process of selective laser melting,the area of the machining regions which is in the same layer may not be equal.If the same laser power and scanning speed are used continuously,the heat accumulation effect of local regions will become more and more serious,resulting in poor molding quality.For this issue,this article introduces a CLI + file format for adding process parameters.By judging the area of the machining regions and adding different laser power and scanning speed,curing the process parameters of selective laser melting is realized.The experiment verifies the feasibility of the CLI+ file and proves that the method can improve the molding quality of the parts.