Comparative Study on the Effect of Nitriding and Microwave Coating on Microstructure, Hardness and Wear of AISI H13 Tool Steel

Abstract

Heat treatment and surface processing are critical aspects of design and manufacture of components in a wide range of industrial sectors. Engineering materials, such as steel, are heat treated under controlled heating and cooling to alter their chemical, physical and mechanical properties to meet desired engineering applications. Gears engaged rotating at several thousand RPM. Inner Barrels of Injection Moulding machines, which is subjected to wear when thermoplastics, glass fibres are chosen to be injection moulded, Guide pillar Guide bush which slide over each other needs to be hardened from outside to improve hardness and wear resistance, but ductile from inside to bear fluctuating load, for this types of operation Case Hardening is required, to give desired property. In this detailed and systematic investigation, we have selected AISI H13 tool steel as for our research work specimen and we have made an effort to find out the mechanical properties (EDX, Hardness HV, Pin on Disc wear test) and micro structural properties (SEM, XRD) by comparing the two process one is traditional Case hardening heat treatment process i.e. Gas Nitriding and a new process i.e. Coating of Ni-based alloy powder on H13 Tool steel by Microwave Hybrid Heating (MHH) method in household microwave oven at 900W and 2.45 GHz and further find the best process. Investigation shows that coated Sample has good Wear resistance as compared to unmodified H13 Tool Steel sample and nitrided sample, Vicker’s micro-hardness of nitride sample is found to be 829.5HV, and for coated sample is 788HV, Coated sample has good Microstructure as compared to nitrided sample and is free from porous cracks.