Improving On Technology For SLS Rapid Prototyping

The Selective Laser Sintering (SLS) is a kind of rapid prototyping (RP) method with using the powder materials accumulative. In the Selective Laser Sintering rapid prototyping, the process methods and parameters will seriously affect the quality of parts, these process parameters include the scanning characteristics of the SLS, the preheat device and the optimization of process parameters. The three aspects are mainly studied in this paper and a certain research results are achieved, which is of referenced value for improving SLS technology and practice.The currently scanning mode of the SLS is similar to the SLA scanning mode which has basically three scanning modes: X-Y, XYSTA, X–X. In the scanning process ,the different scanning rate, the scanning area, the scanning mode and preheat temperature will cause actual sintering temperature too high in some places and which will result in the parts sintered uneven and then affect the quality of parts. The influence law of technology parameters on scanning temperature is researched through experiments. And based on this, some improving measures are put forward in this paper.The main approach of preheat in the existing SLS is to use the tube, this kind of preheating way exists two aspects of weakness: Firstly, the existing preheating temperature field exists serious uneven phenomenon; Secondly , in the preheating process, the tube's open-close will make the temperature fluctuations to 20°C-30°C. This paper analyzes the light road diagram of the preheat device, and using ANSYS to analyze structure, and the relationship between the place of tube installation and the uniformity of temperature field is obtained; at the same time, Using voltage regulator control way to control the temperature of the lamp eliminate the temperature fluctuations in temperature to some extent.The optimization of process parameters has been a key in the study of the process. In this paper, through combining hierarchical and orthogonal and simultaneously taking into account several targets SLS process parameters optimization is made.