Determination of energy during the dry drilling of PEEK GF30 considering the effect of torque

This paper analyses the energy required during the dry drilling of PEEK GF30, a thermoplastic material, polyether-etherketone, reinforced with glass fiber. Three different types of drills are used, respect to material and geometry, under nine cutting conditions based on cutting speed of 6000, 7000 and 8000 rpm, and feed rate of 300, 400 and 500 mm/min. The results show that similar outcomes are obtained with two drills, one of them, wolfram carbide with coating of TiAlN y another of wolfram carbide with point of diamond. This aspect is important due to the economic advantages of the first drill respect to the second one. An analysis of variance, ANOVA, shows that the drill type is the more influent factor, and that the optimal situation can be given with drill of WC and point of diamond with the higher cutting conditions. The energy required, assigned to the torques, is superior to 98%, in each case, question that could be taken in account in the tools design. (C) 2013 The Authors. Published by Elsevier Ltd.