The Effect of Volume Fractions on Hole Stress Concentration in Composite Lamina Subjected to Matrix Plasticity

Electrical discharge machining process، is one of the most widely used methods for machining، the electrically conductive parts. In this way the tool is not in contact with the workpiece and the hardness of workpiece does not affect the machining speed. In Electrical Discharge Machining process، selection of the correct machining parameters are effective in final cost and the quality of the products. The special application of this alloy in various industries including tooling industry is attributed to its high hardness and wear resistance. The DIN 1. 2080 steel at low temperature has a high wear resistance. Its hardness depth is high and it is suitable for machining at low temperature. In this paper، the effect of the type and setting parameters and determination of optimal levels in of electrical discharge machining of alloy DIN 1. 2080 using the Taguchi method and optimal determinant is examined The desired setting parameters including gap voltage، current intensity، on time and off time. The material removal rate and surface roughness of produced parts as the output characteristic of the study were investigated. Results showed that the spark current is more effective on the output parameter (more than 65% on material removal rate and more than 48% on a surface roughness)، Other effective parameters are pulse on time، pulse off time and voltage changes، respectively. Higher current and pulse on time values and lower voltage and pulse off time values result in high MRR and low SR.