Cutting force, tool wear and surface finish in drilling metal matrix composites

摘要

In this paper the evolution of the cutting force, tool wear and surface finish, measured when drilling the metal matrix composite A356/20/SiCp-T6, is presented. The experimental work was developed through the continuous measurement of the torque with an appropriate piezoelectric dynamometer and the results were used to derive the cutting power (ranging from 0.1 to 0.4 kW) and the specific cutting pressure, K{sub}s (1700-3500 N/mm{sup}2). The tool wear type was identified and its evolution with cutting time was measured for different sets of cutting conditions, using polycrystalline diamond drills. The holes' surface finish was evaluated and very good results, exceeding standard values for drilling, were obtained (R{sub}a between 0.25 and 1.2 μm).