Influence of temperature on friction and wear behavior of aps sprayed nicrbsi/flyash and nicrbsi/flyash/tio2 coatings

Abstract

Present work reports on the development of two different NiCrBSi based coatings reinforced with flyash and flyash/TiO<inf>2</inf>. Dense coatings with lamellar structure were establishedvia atmospheric plasma spray (APS) method on nickel based superalloy Superni 76. Coatings were subjected to scanning X-ray deflection and electron microscopy to study the microstructure and phase analysis. Microhardness and elevated temperature wear tests were conducted to analyze the coating hardness, wear andfriction characteristics. Worn surface and wear debris obtained once wear experiment was calculatedvia scanning electron microscopy. Both the coatings exhibited lamellar structure with flyash and TiO<inf>2</inf> particles present at the inter-splat boundaries. Mcirohardness of both the coatings were significantly greater than theSuperni 76 substrate. The wear rate of both the coatings was found to increase with the increase in load as well as temperature. Worn surface analysis revealed mild abrasion and adhesion for NiCrBSi/flyash coatings while brittle fracture for NiCrBSi/flyash/TiO<inf>2</inf> coatings as major wear mechanism. © 2020, Alpha Publishers. All rights reserved.