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

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 degrees, 60 degrees and 90 degrees. During the erosion studies, weight loss and erosion rates in terms of volume loss (mm(3)/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 degrees. 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 degrees and 90 degrees. 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.