Naik, T.Mathapati, M.Prasad, C.D.Nithin, H.S.Ramesh, M.R.2026-02-042022Surface Review and Letters, 2022, 29, 1, pp. -0218625Xhttps://doi.org/10.1142/S0218625X2250007Xhttps://idr.nitk.ac.in/handle/123456789/22866In this study, NiCrC and NiCrSi coatings are deposited on the MDN 310 steel using High-Velocity Oxy-Fuel (HVOF) process. Laser Surface Melting (LSM) post-heat treatment is carried out on as-sprayed coatings using Laser Engineered Net Shaping (LENSTM) with a power of 300W. The characteristics of both coatings in terms of mechanical and metallurgical properties have been investigated. The thicknesses of the as-sprayed NiCrC and NiCrSi coatings are in the range of 170-200μm. Laser-treated NiCrC and NiCrSi coatings exhibit a thickness range of 162-185μm, respectively. The microstructure of laser-treated NiCrC-300W coating clearly shows a dendrite-like structure, whereas the laser-treated NiCrSi coating exhibits hard layer and columnar homogeneity. Microhardness of as-sprayed NiCrC coating is 515±15 HV0.3 and that of NiCrSi coating is 645±25 HV0.3. Microhardness of laser-treated NiCrC coating is 720±30 HV0.3 and that of NiCrSi coating is 890±15 HV0.3. Dry sliding wear tests are conducted at room temperature (RT) and 400°C with 10-N and 20-N loads. The wear rates at 400°C temperature of laser-treated NiCrC and NiCrSi coatings produced are slightly below (1-2.2)×10-3mm3/m and (0.8-1.6)×10-3mm3/m, respectively. Laser-treated coatings produced better dry sliding wear behavior compared with as-sprayed coatings owing to dense microstructure. Formation of SiC phase in NiCrSi coating imparts high wear and frictional resistance compared to the NiCrC coating. © 2022 World Scientific Publishing Company.ChromiumChromium alloysFrictionFuelsHVOF thermal sprayingMeltingMicrohardnessSilicon alloysSilicon carbideSprayed coatingsWear of materialsWear resistanceHigh velocity oxy fuelLaser surface meltingLaser treatedMicro-structuralNickel chromiumPost heat-treatmentPost treatmentPost-heat treatmentSliding wearSliding wear behaviourMicrostructure