Papers by Author: Hazoor Singh

Abstract: Erosion behavior of the high velocity oxy fuel (HVOF) deposited Cr₃C₂-NiCr and WC-Co coatings on boiler tube steels was evaluated. The solid particle erosion study was conducted, using an air jet erosion test rig at a velocity of 26 m/s and impingement angles of 30⁰ and 90⁰, on uncoated as well as HVOF spray coated boiler tube steels at 250°C. The coatings are significantly harder than the substrate steel and less porous. Scanning electron microscopy (SEM) technique was used to analyze the eroded surface. Mass loss of the coatings was found higher than the boiler tube steel.

Abstract: Wear behavior of the HVOF deposited NiCr and Stellite-6, coatings on Fe-base alloy steel were evaluated by the pin-on-disc techniques. The coatings were significantly harder and less porous. SEM/EDAX and XRD techniques were used to analyse the worn out surface and wear debris. The Fe₂O₃ was identified as the major phase in the wear debris. The wear mechanism is mild adhesive wear in nature. The coatings protected the substrate steels against the adhesive wear significantly.