Optimized Design and Direct Manufacture of a Clearance Feature in a Non-assembly Mechanism by Selective Laser Melting (SLM)
Y. Liu, Y. Yang and D. Wang
The clearance feature is the key issue in the direct manufacturing of nonassembly mechanism by selective laser melting (SLM). Although support structures can prevent warpage and collapse of overhanging surfaces within the clearance feature during the laser beam irradiation, the motion performance of mechanism is however reduced. Taking the avoidance of an overhanging surface within the clearance as the goal in this study, the critical building angle of overhanging structure was determined as 40o, and influences of process parameters on clearance size were studied. Furthermore, optimized structures of kinematic pairs were proposed to reduce the overhanging surfaces. Finally, the optimized kinematic pairs were applied to a typical mechanism. The result shows that mechanism can be manufactured perfectly by using the optimized kinematic pairs and process parameters without considering the overhanging surfaces within clearance feature.
Keywords: Fibre laser, 316L stainless steel, non-assembly mechanism, selective laser melting (SLM), clearance feature, kinematic pair, overhanging surface, support structure, optimized design.