Abrasive Wear Behaviour of High-Velocity Oxy-Fuel Sprayed Molybdenum–10 wt Silicon Carbide Composite Coatings

摘要

Abstract The abrasive wear behaviour of high-velocity oxy-fuel sprayed molybdenum–10?wt SiC composite coatings deposited on A36-grade steel is discussed in this paper. Molybdenum is a refractory metal with a high elastic modulus, and silicon carbide has an excellent hardness; the two can be combined to create composite coatings with exceptional mechanical properties. The developed coating was uniform, and the thickness ranged between 200 and 230?m. The abrasive wear resistance of coated and uncoated specimens was tested using an ASTM G65-C dry sand rubber wheel abrasion test rig. The properties of the Mo-10?wt SiC composite coating, as well as their performance in abrasive wear tests and mechanisms, were investigated. When the surface properties of coated and uncoated specimens were compared under similar conditions, the Mo-10?wt SiC composite coating on substrate exhibited a 12 reduction in volume loss and a 1.75?times increase in hardness when compared to the uncoated substrate. The specific wear rate for composite coating is 15 lower than for A36 steel substrate, but the wear coefficient is 35 higher, owing to the composite coating's increased hardness. The wear resistance of a material to abrasion is an important consideration in determining its wear behaviour, and for the composite coating, it is found to be 13 higher than that of the A36 steel substrate. SEM and 3D confocal studies confirm good interfacial bonding and minimal surface damage during abrasion testing with a Mo-10?wt SiC composite coating.