Electrical discharge machining studies of al tic composites processed through powder metallurgy technique

Abstract

The present research work focuses on the experimental investigation and optimization of machining parameters of Electrical Discharge Machining of Aluminium and Titanium carbide Metal Matrix Composites. The matrix material used is Pure Aluminium with three grades AP 50, AP 60 and AP 80. The Titanium carbide with 2.5% by weight, 5% by weight and 7.5% weight is used along with each grade of Aluminium. Hence 9 different combinations of powder mixture were used to produce the specimen. Powder metallurgy method was adopted to prepare nine combinations of composite materials. The specimens for the mechanical testing were prepared according to the ASTM standards. The micro structural analysis was implemented by employing a scanning electron microscope to appraise the spread of the particles in the aluminum matrix. Experimental investigations were made with Electrical Discharge Machining (EDM) process to find the impact of the process parameters on Metal Removal Rate (MRR) and Surface Roughness SR. The Pulse on Time (Ton in micro seconds), Pulse off Time (Toff in micro seconds) and Peak current (Id in Amperes) are the input parameters. The experiments were conducted by following the guidelines of Taguchi s approach using orthogonal array. Analysis of variance (ANOVA) was formulated to obtain the most significant factors in the achievement of competent machining. newline