Solid particle erosion of HVOF sprayed NiCr and Stellite-6 coatings

Solid particle erosion behavior of the HVOF deposited NiCr and Stellite-6, coatings on boiler tube steels was evaluated. The study was conducted, using an air jet erosion test rig at a velocity of 26 m/s and impingement angle of 30° and 90°, on uncoated as well as HVOF spray coated boiler tube steel (GrA1) at 250 °C. The coatings were harder as compared to substrate steel. Scanning electron microscopy (SEM) technique was used to analyse the eroded surface. Mass losses of the coatings were found marginally higher than the boiler tube steel.