Micro-milling of unreinforced and reinforced polypropylene

It is essential to determine the micro-machinability performance of polymer and glass fiber-reinforced polymer composite in order to effectively utilize the polymer and its composite as an engineering material at the micro-scale world. However, a literature survey revealed that not much work was done on the micro-milling of polymer and its composite. In the light of literature surveys, it can be said that the novelty of this study is to investigate the micro-milling performance of polypropylene and glass fiber-reinforced polypropylene manufactured with plastic injection molding process. The tests were performed at different feed rates and spindle speeds and the effect of these parameters on tool wear, burr width and micro-milling forces was investigated. In general, it was concluded that wear and forces in micro-milling of reinforced polypropylene composite were higher than that of unreinforced polypropylene. Micro-milling forces increased with feed rate and spindle speed for both materials. The lowest top burr size and force values were obtained at the feed of 50 mm/min and the spindle speed of 20,000 r/min. Unreinforced polypropylene gave better performance with respect to glass fiber-reinforced polypropylene composite from micro-machinability aspect.