Modeling of burr size in drilling of aluminum silicon carbide composites using response surface methodology

Abstract

Exit burrs produced during various machining processes degrade the product quality and functionality of different parts of assembly. It is essential to select the optimum tool geometry and process parameters for minimizing the burr formation during machining. In this paper, the effects of cutting speed, feed rate, point angle of drill bits and concentration of the reinforcements on the burrs produced were investigated. Response surface methodology has been adopted to create the quadratic model for the height and thickness of the burrs produced during drilling of AlSiC composites. Analysis of means and variance were used to find the significance of the process parameters on the responses and to find the optimum combination of parameters to minimize the burr formation. Feed rate, point angle and concentration of reinforcements in the matrix are found to be the significant factors. Both the responses were found to be minimum for lower feed rate, higher point angle and higher concentration of reinforcements. Scanning electron microscopy was used to understand the mechanism of burr formation.