Abstract
This paper presents the adhesive strength results of copper and titanium deposits produced by cold spray processes on steel, stainless steel, aluminum and copper substrates. We investigated how the combinations of the particles and the substrate, and the pressure in the cold spray nozzle chamber affect the adhesive strength between the deposits and substrates. We used nitrogen and helium as cold spray process and powder carrier gasses in the processes. We found that helium gas produced much higher adhesive strength than nitrogen and that the strength of the deposits produced by using both helium and nitrogen gases was almost proportional to the chamber pressure. The adhesion produced by cold spray processes appeared to be dependent on the combination of hardness of powder and substrate metals. We also present cross section micrographs of the deposits and substrate observed after tensile strength tests. They show the substrate which is soft or easily deformed by particle collisions generates strong adhesion.
