A study on the effects of input parameters on the surface integrity of AISI H13 tool steel in Electrical discharge machining

In this paper the effect of input parameters of the EDM process (pulse on-time، duty cycle and tool polarity)، on the surface integrity (surface roughness، density of surface crack، and white layer thickness) in the machining AISI H13 tool steel has been studied. The result of this research shows that in the positive tool polarity the white layer thickness and density of surface cracks in the low pulse on-time are higher than that of the tool polarity chosen to be negative. However in the negative polarity in the high pulse on-time، density of surface cracks and the thickness of the white layer are higher on the machined surface. Moreover، according to the obtained results، density of surface cracks and the average of the white layer thickness is reduced when the duty cycle increases in the two conditions of tool polarity. By the increase in the pulse on time، the amount of surface roughness is increased.