Improvement of Surface Properties of AISI H13 Tool Steel by Electrical Discharge Deposition Using (Ti - Cr - Cu) Alloys

In this paper, effect of input parameters (pulse on time, pulse current, voltage and duty cycle) of electric discharge deposition process on surface quality parameters including surface hardness, surface deposited layer thickness and roughness of AISI H13 tool steel using Ti-Cr-Cu alloys as electrode was studied. SEM was used to investigate the thickness of the surface layer, and the hardness of surface deposited layer was measured by microhardness test. Also, XRD method was used to identify the compounds on the surface and deposited surface roughness was controlled using Ra parameter. Based on the obtained results, TiC, Cr7C3 and Fe2C are formed at the deposited layer due to surface alloying and increasing surface hardness. Also, by increasing the pulse current and the pulse on time, the surface hardness and depth of the deposited layer were increased. Furthermore, with increase in input voltage, the thickness of the surface layer is increased and the workpiece surface roughness is reduced. Also, by increasing the duty cycle due to the increase in the number of sparks in time, the depth of the surface deposited layer is increased.