The Influence of the Process Parameters on the Properties of Detonation Sprayed WC-12Co Coatings

Abstract

Abstract In recent years, the thermal spray technique has emerged as the most useful method for developing a wide variety of coatings which enhance the performance and durability of engineering components exposed to diverse forms of wear. Among the thermal spray techniques, detonation spray coating (DSC) has retained its position as one of the best available techniques for obtaining dense, wear-resistant coatings. Notwithstanding the advantages of the DSC technology over other thermal spray variants, the understanding of the fundamental aspects of this technology is still extremely limited. In view of the above, a major programme has been undertaken in this laboratory to assess the parametric impact of the key DSC process variables (oxy-fuel ratio, spray distance, powder feed rate and shot frequency) on the mechanism of coating formation and the properties of the resulting coating. As a part of the above exercise, the key DSC process variables have been varied systematically employing a statistical design and the properties of the WC-12Co coatings so obtained have been evaluated. The results of such a study are presented in this paper. In particular, it has been demonstrated that useful conclusions regarding the influence of process parameters on the properties of the WC-12Co coating cannot be reached unless the scatter in the experimentally measured coating property data is also simultaneously taken into account.