Effect of Spraying Parameters on the Bonding Strength of Detonation Sprayed WC-Ni Coatings

Abstract Well-known detonation thermal spraying is considered to be a good method for the preparation of WC-based coating with high adhesion. The depositing parameters, especially the oxygen-fuel ratio and spot frequency, have been observed to influence the properties of the coating. The influence of the main parameters of the detonation spraying of tungsten carbide based coatings and their mechanical properties have been investigated. Two main tasks for the development of a carbide-containing material application technology have been determined. The relationship between the phase composition of WC-based coatings and their strength, hardness and bond strength to the substrate has been identified. The technique of coating in the reductive mode has been proposed. High oxygen-fuel ratio and spot frequency decreased the decomposition of the WC-phase, which makes the WC-Ni particles harder and as a result more easily embedded in the substrate, i.e. the coating which is beneficial to enhance bonding strength.