Direct laser metal deposition cladding of IN718 on DIN 1.2714 tool steel reinforced by the SiC nanoparticles

Abstract

Due to ever-present applied pressure and thermal shocks, forged dies are in danger of durability and hardness reduction, surface cracks formation, and failure. Therefore, this study aims at investigating the effect of Direct Laser Metal Deposition Cladding (DLMD) power and powder composition as a repairing technology on mechanical properties and the microstructure of the forging dies fabricated out of hot work steel DIN 1.2714 (56NiCrMoV7). IN718 was used as the DLMD powder. However, its low wear and friction resistibility had already been improved via SiC nanoparticles. Results indicated that compared to pure In718, adding up to 5 wt% of SiC nanoparticles to IN718 increased its wear resistance and microhardness by 51% and 50%, respectively, and induced a 129% reduction in its friction coefficient. On the other hand, a laser power of 450 W led to a 127% and 112% increase in wear resistance and microhardness of the coating in comparison to a laser power of 450 W.