Cold spray is an additive manufacturing technique where solid powder particles bond with a target substrate upon high-velocity impact. It offers advantages over traditional coating methods, preserving materials' properties without harmful by-products. While extensively researched for metal-on-metal coatings, cold spray's application to polymers is relatively new. This dissertation comprises three studies focusing on cold spray of polymers. The first investigates coating metal substrates with polymeric powders, a topic with limited prior research. It systematically examines parameters such as particle and substrate temperature, substrate surface roughness, and the effect of priming on deposition efficiency and adhesion strength. The results indicate that there exists a deposition window of velocity, impact angle and temperature for good deposition, and the spray parameters need to be maintained within this window. The second study explores using polymer composites in cold spray. Nano-sized copper and silicon dioxide particles are added to high-density polyethylene (HDPE) to create composites. The research examines how concentration, particle size, and impact energy affect deposition. Results show that copper and SiO2 behave differently when added to HDPE, and there is not a monotonic increase in the efficiency of the cold spray process with the increase in the filler material. Instead, an optimal particle concentration is found for each composite powder that maximizes the deposition efficiency. This optimal concentration varies with particle size and type. The third study investigates adding carbon nanotubes (CNTs) to HDPE powders. CNTs are known for their exceptional properties including strength, toughness, and electrical and thermal conductivity. The research demonstrates that both the composite powder processing and the cold spray process itself significantly influence the morphology, distribution, and orientation of CNTs within the HDPE matrix, and consequently, the properties imparted by the CNTs. Notably, the cold spray process is found to positively impact CNT orientation in the final deposit, which can be inferred from the enhanced electrical conductivity of the CNT-HDPE deposit. These findings offer valuable insights into creating polymer composite coatings using cold spray and establish it as an efficient alternative to conventional coating techniques.