Microstructure and corrosion performance of cold-sprayed AA7075 MMC coatings

Dual-reinforced aluminum alloy 7075 metal matrix composite coatings were cold-sprayed with varying boron carbide and graphene nanoplatelets amounts. The influence of the reinforcements and particle deformation flattening ratio (FR) on the microstructure and corrosion behavior of coatings was investigated. Microscopy revealed higher flattening ratios and improved density, leading to reduced electrolyte penetration. Excessive reinforcement led to micro-galvanic effects and weaker interfacial bonding, which accelerated localized corrosion. These results highlight the role of reinforcement dispersion and FR in the corrosion resistance of cold-sprayed coatings.