Rapid manufacturing of metal-ceramic composites

This paper presents a layer manufacturing technology called selective laser gelling (SLG) to fabricate metal-ceramic composites green parts which are difficult to construct using traditional methods for fabricating composites. When a layer of metal-ceramic slurry is scanned via Nd: YAG laser radiation, the metal particles are gelled together by the silica sol to form a composites part. In comparison with other composites processes, the features of this process include lower laser forming energy, faster fabrication speed, less dimensional variations. The material composition is mixing by the stainless steel powder and a silica sol in a proportion of 75 to 25 wt. %. A series of experiments was conducted to obtain the smallest pave-able layer thickness of 50 mu m on an experimental rapid prototyping (RP) machine. The feasibility of this process was demonstrated by manufacturing a gear shaped prototype with a surface finish of 18 mu m under a laser energy density of 3.5 J/mm(2).