The Improvements And Experimental Research For The Preheating Control Device Of SLS

Selective Laser Sintering(SLS) is a kind of rapid prototyping method which sinter layered powder with laser,and then the sintered layer overlap to form parts indifferent shapes. The stability of preheating temperature and the accuracy of powder’s laying affect the accuracy of the molded parts in SLS technology. This paper focused on the research and improvement of preheating and powder laying device of XJRP-SLS400molding machine, which has important realistic meaning for accelerating the industrialization of the molding machine.The existing XJRP-SLS400molding machine was using solid-state relay control the preheating tubes to complete preheating process.there are two problems with this approach. Firstly, turning on or off the tubes will cause cause lager temperature fluctuations; Next, four lamp-heated temperature field is uneven distribution. This paper puts forward a new preheating way using variable heating power in which we can adjusts the lamp power according to the temperature difference between the temperature of heating surface and the preset temperature. Aiming at the uneven of the temperature distribution, this paper analyses the laws of temperature distribution of the tubes and designs relative experiments then puts forward improved measures to make the heating surface temperature distribution more uniform.The way of existing molding machine’s laying powder using a scraper to push the powder move ahead, the deficiency of which is the powder in the plane is not compact enough, and always cause moving of the already formed part which stopped the molding process. This paper uses roller instead of scraper to spread the powder, analyses the motion parameters then uses a mathematical method to describe the movement of the roller to research the influence of the motion parameters on the quality of powder spreading.