The effect of cutting parameters and tool geometry on machinability of cotton-fiber reinforced polymer composites: Cutting forces, burr formation, and chip morphology

Due to the increasing importance of natural fiber reinforced polymer composites, a large number of papers published about fabrication of these materials, but yet the secondary manufacturing performance knowledge of such materials is rather limited. Understanding cutting performance of a novel natural fiber (cotton) reinforced polymer composite is the primary interest of this work. In the first part of the study, suitable cutting tool geometry was designated through milling tests and the results of cutting force, burr formation, and chip morphology. One flute left helix WC (Tungsten Carbide) tool was the most suitable tool geometry for cotton-fiber reinforced polymer milling. The optimum cutting parameters were selected with the designed quantitative scoring procedure for combined evaluation of cutting force and burr formation results. According to the evaluation system, the optimum cutting parameters were found as 25 m/min cutting speed and 200 mm/min feed rate. Three form of burr which are roll-over, poisson and entrance burr, and short ribbon shape chips with linty look were observed due to the embedded cotton fibers in LDPE matrix. At the end of the study, the benchmarking cutting force tests were conducted with pure low density polyethylene material and results compared with the cotton-fiber reinforced polymer.