Characterization of cold-spray coatings on fiber-reinforced polymers through nanoindentation tests

Polymer matrix composites are finding never-ending widespread uses in the last decades; one recent tendency is to metallize their surface to further widen their field of application. Cold-spray deposition is one of the most promising techniques that can be adopted to this aim. Cold-spray deposition on polymers is in its early stage and more experimental work is required to fully understand the phenomena ruling the deposition. In this paper, the results of nanoindentation measurements on cold-spray coatings on various substrates will be presented and discussed. Polypropylene was used as matrix while carbon and glass fibers have been used as reinforcement, both steel and aluminum have been used as feedstock material for the cold-spray deposition. Nanoindentations tests have been then carried out on all the different samples; the influence of the fibers and of the powders sprayed on the behavior of the coatings is discussed in light of the experimental outcomes.