Thermal Spray Metallization of Polymers: A Review of Hybrid Polymeric–Metallic Coatings

In recent years, the quest for advanced materials has intensified, driving the exploration of innovative coating systems to enhance material properties. Polymeric materials, renowned for their adaptability, have found extensive use across various industries. However, their inherent limitations in mechanical strength, wear resistance, and thermal stability have prompted researchers to seek enhancement avenues. Hybrid polymeric–metallic coatings have emerged as a promising solution, employing thermal spray techniques to metalize polymeric substrates. This amalgamation utilizes the versatility of thermal spraying methods, ranging from cold spraying, flame spraying, arc spraying, to plasma spraying, to achieve robust adhesion between metal and polymer layers. These techniques yield durable composite structures, fortifying surfaces against corrosion and wear while enabling dimensional restoration. Cold spraying, in particular, stands out among thermal spray methods due to its effectiveness in metalizing various materials. This comprehensive review delves into recent advancements in hybrid polymeric–metallic coatings via thermal spray processes. Emphasis is placed on analyzing critical factors influencing coating properties, including various thermal spray parameters. Furthermore, the paper scrutinizes the challenges and future potentials inherent in thermal spray techniques, with a focused exploration of cold spray technology. Understanding these methodologies is pivotal for optimizing the design and durability of structural materials made of polymers or composites.