Relationships between in-flight particle characteristics and coating microstructure with a twin wire arc spray process and different working conditions

The aim of this study is to get a better understanding of the build up of coatings obtained through twin wire arc spray process. Properties of in-flight steel particles, i.e. diameter, velocity and temperature, were determined using a dpv system, for different working conditions. Due to very large size distribution, specific experimental set-up has been developed in order to collect particles at a given spraying distance. As a result, the dpv diameter parameter was calibrated and well-marked tendencies on particle velocity and diameter have been found while changing input parameters. Then, the morphology of the splats has been studied in terms of flattening degree and shape factor. Finally, some correlations have been established between input parameters and properties of coatings in relation with particle characteristics and splats analysis.