The effects of reinforcements and heat treatment on the tool performance during machining of metal matrix composites

Abstract

Machining of metal matrix composites (MMCs) has been considerably difficult due to the extremely abrasive nature of the reinforcements that causes rapid tool wear and high machining cost. In this study, the effect of T6 heat treatment, cutting parameters and weight fraction of reinforcement on the machinability of 7075Al/Al 2 O 3 composites was investigated because of tool wear. Machining tests were performed on both as-cast and heat treated aluminium matrix composites reinforced with 10% and 25% weight fractions and 16 µm average size of Al 2 O 3 particles by turning process using physical vapour deposition (PVD) coated carbide tool CP500 at different cutting conditions. The analysis of variance (ANOVA) was also employed to carry out the effects of these parameters on the cutting tool life. It was concluded that in both as-cast and heat treated composites the tool life decreased with increasing the cutting speed, feed rate and weight fraction of particles. However, heat treatment improved significantly the tool life. For the tool life, particle content was found to be the most effective factor followed by heat treatment and cutting speed respectively.Reference to this paper should be made as follows: Kök, M. (2013) 'The effects of reinforcements and heat treatment on the tool performance during machining of metal matrix composites', Int. J. Machining and Machinability of Materials, Vol. 13, No. 1, Biographical notes: Metin Kök is an Assistant Professor at Kahramanmaraş Sütçü Imam University. He studied mechanical engineering, branch: manufacturing and construction. He holds a PhD on production and machinability of metal matrix composites reinforced with particulates. His fields of activity are particle reinforced metal matrix composites, machinability, cad-cam, cnc machines.