Surface Roughness and Cutting Forces During Edge Trimming of Multi-directional Carbon Fiber Reinforced Polymer (CFRP)

Carbon fiber reinforced polymers (CFRPs) have found wide-ranging applications in numerous industrial fields especially in aerospace as well as automotive industries due to their excellent mechanical properties such as high strength, low weight and corrosion. The aim of the present work is to investigate the effect of machining parameters on surface quality and cutting forces in edge trimming process for a specific CFRP material. There were two variation of machining parameters focused in this work namely spindle speed (N) and feed per tooth (fz). The range of spindle speed applied was of 2506 rpm (low), 5012 rpm (moderate), and 7518 rpm (high) speed whilst for feed per tooth; 0.05, 0.1, and 0.15 mm/rev. The CFRP panel measured 3.25 mm in thickness and the type of fabric was unidirectional (UD) with 28 number of plies in total has been chosen to be the main study material. Router or burr tool geometry made of uncoated tungsten carbide with a diameter of 6.35 mm was used to perform the edge trimming process. Surface roughness measurement was taken using Mitutoyo Surftest SJ-410. Kistler Type 9257B dynamometer is attached during the edge trimming process to record the cutting forces. The result reveals that the smallest value of the surface roughness (1.62 µm) is obtained by Run 1 (R1) and the highest surface roughness value (12.62 µm) exhibited by the R9. The resultant force exhibits no clear trend on the cutting forces for all the machining parameters applied. However, it is strongly believed that the thermal effect especially the low temperature of glass transition, Tg of the polymer matrix was the main reason affecting the result of the resultant force. Details results elaborated and discussed further in this manuscript.