Study On The Optimization Of Process Parameters Of Stereo Lithography Apparatus

Rapid prototyping of stereo lithography apparatus is the earliest developed in rapid prototyping manufacturing technology. It is also studied more in-depth in rapid prototyping technology in the present. This technology is not only suited for the development of the new product, the manufacture of the irregular or complex shapes such as aircraft models and wind tunnel model of complex-shaped surfaces, appearance evaluation and assembly inspection, rapid reverse engineering and replication, but also suited for the manufacture of difficult materials. The technology is not only broadly applied in manufacture, but also has the broad application prospects in many fields such as materials science and engineering, medicine, culture and art and so on.In recent years, the rapid prototyping machine of stereo lithography apparatus that its main light source is UV light has been developed in our country. The cost of this type of machine and operation are significantly lower than the laser machine, but its accuracy is poor. This paper focuses on the problems of UV rapid prototyping accuracy as the main object. A large number of the basic experiments have done on basis of the theoretical analysis by the experimental equipment of the CPS350 rapid prototyping machine.In this paper, the basic principle of stereo lithography apparatus is deeply described. And the various factors on forming accuracy in three stages of the shape of the pre-data processing, forming and post-treatment process are analyzed systematically.The swelling problem of photosensitive resin has been analyzed. The special-shaped piece is modeled and data collected by the reverse technology, and the further experiments have been done for the size deviations and its changing law. The rule that the resin characteristic, scanning length and acceleration and deceleration of the scanning system affect the part precision is obtained. The improvement measure that the light scanning motion control system adopts varying accelerated motion during reversing stage is brought out. The view of increasing the controllable shading system will be proposed for X-type defects in the experiments. Because there are many process parameters can influence the precision of rapid prototyping part, this paper is based on the size errors of three direction's dimension as measuring index, the four factors and three horizontal orthodoxy experiments are designed. Using the method of the analysis of variance, the rules are studied that how the scanning speed, facular compensation, layer thickness, and scanning space affect the forming quality and the optimal process parameters combination of stereo lithography apparatus in certain extent is obtained.Meanwhile, the measures to improve the precision of the molding parts are proposed, which could be the guidance to the development of ultraviolet light rapid prototyping technology.