Research On Abrasive Water Jet Polishing Process For SLA Prototype

Stereo Lithography Apparatus (SLA) technology based on disperse and accumulate theory can produce prototypes with delamination rapidly, but it can not avoid the small steps on the prototype surface which are brought by delaminating manufacture technology. The small steps on the prototype surface affect the surface roughness of the prototype, and result in the precision loss. So we must polish the prototype surface to make it not only smooth and brightness, but also clean and wipe off other things. Because the prototype material have special physics and chemical character, the geometry shape of prototype surface are commonly complex, it is very hard to be polished by general polishing progress.Polishing technique of Abrasive Water Jet (AWJ) is an advance process which can be applied to surface polishing. It makes use of high velocity polishing liquid which has tiny abrasive to impact and cut the work-piece surface material for polishing purpose. AWJ has inimitable advantages which compares with the tradition polishing techniques to polish the SLA prototype surface. It not only can polish the prototype surface which has very complex geometry shape, but also can not be limited by physics and chemical character of the prototype.In this article, the feasibility of using AWJ technique to polish the SLA prototype surface has been decided by analyzing the theory of AWJ technique and researching the prototype material physics and chemistry characters. The polishing technique of AWJ for the prototype surface has been studied. The relation between the surface roughness of the prototype and some technique parameters such as jet pressure, distance, angle and time has been discussed. The affect curves about the prototype surface roughness and some technique parameters are given. The better polishing technique parameters have been gained by using orthogonal experiment test. When the jet pressure is 1. 4MPa, the distance is 5mm, the angle is 45° , the time is 30min ,the better surface roughness and the material wipe off ratio will be got by the polish experiment. The article will provide the stability base of theory and experiment for auto polishing the SLA prototype surfaces which have complex shapes.