The Benefits of the PROTAL Process on the Adhesion of Thermal Sprayed Coating

In this paper, the authors evaluate the effect of different laser parameters on the adhesion of coatings produced by the Protal method. The process incorporates an atmospheric thermal spray torch and a pulsed Nd:YAG laser, achieving surface preparation (comparable to grit blasting) and coating deposition in a single step. Coating adhesion was measured via tensile testing and an indentation method, and the rupture areas (along with some of the coating-substrate interfaces) were examined using SEM techniques. The results show that with the new process chemical and metallurgical bonding can be achieved between the substrate and coating by spraying in air.