Polymer matrix composites (PMCs) have become one of the most widely used engineering materials due to both the developments in polymers and advanced fillers. It is expected that polymer composites will take their final shape during the production phase, which means that they are not required to undergo new processes. However, in some applications, machining operations, such as turning, milling, grooving and hole drilling, cannot be avoided and thus, finishing operations must be applied to these materials. Since these materials have complex microstructures, finishing operations may cause situations that adversely affect engineering properties, such as matrix cracking, delamination, debonding, etc. In this study, micro-milling operations were performed for recently developed ceramic reinforced polymer composites. Three different spindle speeds were used while feed rate and cutting depth were kept constant in the operations. The composites were produced from powdered UHMWPE and silicon carbide particles. Several parameters were varied in the production of the composites, such as molding pressure, filler loading and filler size. The investigated outputs were cutting temperature and surface roughness, whereas machined surfaces and chip morphologies were also investigated via microscopy analyses. In the final stage, regression analyses were performed to investigate the relationships between the process parameters. According to the results, ceramic reinforced polymer composites exhibit different machinability properties than fiber-reinforced ones due to hard fillers and low melting point of UHMWPE.

Click for detailed information.