Erosion Studies of D-Gun-Sprayed WC-12%Co, Cr3C2-25%NiCr and Al2O3-13%TiO2 Coatings on ASTM A36 Steel

Abstract

Solid particle erosion studies were conducted in simulated coal-fired boiler environment in order to compare the erosion behavior of three different types of detonation gun (D-Gun)-thermally-sprayed coating powders, i.e., WC-12%Co, Cr3C2-25%NiCr and Al2O3-13%TiO2 on ASTM A36 steel and bare ASTM A36 steel. Erosion studies were conducted by using an air jet erosion test rig at impact angles of 45°, 60° and 90°. During the erosion studies, weight loss and erosion rates in terms of volume loss (mm3/g) were determined by using an optical profilometer. WC-12%Co-coated specimens exhibited the behavior closer to the behavior of ductile materials, whereas Cr3C2-25%NiCr- and Al2O3-13%TiO2-coated specimens exhibited the typical behavior of brittle materials. All the three different types of D-Gun-sprayed coating powders had successfully protected the ASTM A36 steel from solid particle erosion at an impact angle of 45°. Out of the three different types of coatings, two coatings, i.e., WC-12%Co and Cr3C2-25%NiCr, had successfully protected the ASTM A36 steel from solid particle erosion at impact angles of 60° and 90°. This paper evaluates the solid particle erosion behavior of bare and coated ASTM A36 steel which will be helpful in choosing the suitable coating for induced draft fan applications.