Effect of SiC nanoparticles on properties of laser cladding IN718 coating

Nickel-based superalloys, such as IN718, exhibit superior corrosion and oxidation resistance under high-temperature and high-pressure conditions, rendering them suitable for aerospace applications. This alloy retains its strength across a broad temperature range and finds application in scenarios where aluminum and stainless steel cannot withstand creep at superalloy temperatures. However, its relatively low hardness and wear resistance limit its utilization in certain areas. To enhance the wear resistance and hardness of laser-cladded IN718 coatings, SiC nanoparticles were employed as reinforcements. This study evaluates the effect of SiC nanoparticles in laser cladding on the hardness and wear resistance of DIN 1.2714 hot work tool steel (56NiCrMoV7). Four powder samples with SiC nanoparticle contents of 0%, 1%, 2%, and 3% by weight were prepared. The microhardness, wear resistance, and microstructure of IN718/SiC coatings were investigated. The results show that cladded coating without cracks can be obtained when the SiC nanoparticle content is less than 2 wt%. Mechanical tests showed that the hardness of reinforced layers was increased by about 46% and the high-temperature wear volume of SiC nanoparticles reinforced coating was decreased by about 70% compared to the pure IN718 coating.