Preparation of adhesive coatings from thermally reactive binary and multicomponent powders

The method of preparing an adhesive layer on a substrate includes introducing a thermally reactive powder comprising aluminum and a second metal into a plasma torch, wherein the thermally reactive powder is substantially free of binder, additive and contaminant and does not contain a significant amount of intermetallic compound into a plasma torch. An exothermic reaction is initiated within the thermally reactive powders in the plasma torch and the exotherming powders impinge onto a substrate, such that the heat generated by the exothermic reaction is generated predominantly on the substrate.