Preliminary Analysis of Temperature History When Milling Polymer Matrices for Fibre Reinforced Composites

This paper addresses the temperature effects in abrasive milling of polymer matrices used in fibre reinforced polymers (FRP). Current knowledge of fibre reinforced polymers machining still remains understudied and involves challenging issues for their optimal use. A design of experiments including three matrix types was constructed to analyse the heat distribution due to cutting conditions. The cutting speed N, depth of cut a_p, and feed rate V_f were kept constant in this study. Milling tests were performed on resin specimens using an abrasive grinding wheel and 5-Axis CNC Machine with maximum spindle of 12,000 rpm. Three resinous matrices, namely, polyamide, Epoxy and Polyester were considered for the design of experiments. Equidistant thermocouples type K were embedded within the median plan of the specimen in order to record the temperature histories during cutting step. Measurements showed unequal temperature peaks on the three matrices referring to heat losses irrespective to matrix type. Temperature distribution within the specimens informs about heat evacuation during tool advance. The temperature histories reveal three typical regions regardless the matrix type being milled: fast heating period, maximum peak, and a relatively longer cooling period giving rise to room temperature. Those three periods vary sensitively with the resin properties.