The low temperature Kinetic Metallization (KM) deposition process is compliant with the recently revised MIL-STD-3021 standard for cold spray materials deposition. KM deposition process and equipment was supported through the US Military via multiple Small Business Innovative Research (SBIR) grants leading to delivery of KM deposition equipment to multiple branches. Coating application areas discussed in this paper include wear resistant tungsten-carbide and chromium-carbide hard-phase coatings. These are used for aircraft engines and landing gear surfaces with firm low temperature deposition requirements. Other areas include aluminum and magnesium dimensional restorations, in particular for Aircraft Mounted Accessory Drive (AMAD) gearboxes for F-18 platforms, and land vehicle housings and casings for the US Marines Corps.

Ceramic tiles are widely used as ballistic armor due to their ability to absorb high specific impact energy. However, ceramic materials often exhibit very low ductility and have a tendency to exhibit multiple fractures in spider-web patterns around the point of impact. One method used to introduce ductility is to encapsulate the tile in a metal jacket, or to provide a strongly adhered metallic backing plate. Aluminum and titanium metals are of primary interest to decrease the overall weight of the armor material system. The low temperature Kinetic Metallization (KM) process allows direct deposition of the metals onto the ceramic tiles. This is not possible with thermal spray processes due to the extreme mismatch in thermal expansion and adverse metallic-ceramic chemical reactions at high temperatures. Kinetic Metallization has been used to deposit aluminum and titanium coatings onto silicon carbide (SiC) and proprietary ceramic matrix composite (CMC) tiles. Ballistic testing of coated tiles has shown decreased fracturing of the armor material, leading to improved performance for subsequent impacts.

The repair of damaged Ion Vapor Deposition Aluminum coatings on high strength steel aircraft components has generally required the use of brush plating with hazardous materials including cadmium. Inovati has developed a unique Al-Trans (aluminum-transition metal) coating using the Kinetic Metallization process that permits repairs of IVD-Al coatings on high strength steels. Originally the Al-Trans coating formulation was developed for commercial application on telecommunication equipment steel racks as an electrically conductive grounding strip with excellent corrosion resistance. Recent research was completed with NAVAIR to further develop this coating formulation and the Kinetic Metallization process for repair of IVD-Al coatings on aircraft components. This presentation will describe the KM repair process and the tests completed to qualify the repaired coatings. Inovati has recently developed a KM-Mobile Coating System with a handheld Spray Gun for the field repair of corrosion damaged magnesium and aluminum alloy aircraft components.

Pure Al coatings were fabricated on Cu substrates via kinetic spraying for double-layered Cu liner. The coatings need to endure the high strain rate severe plastic deformation during explosion, in this study, the process optimization of Al deposition was initiated with a definition of “critical velocity” of Al particle in kinetic spraying on a basis of numerical modeling and computations using ABAQUS finite element codes. The simulation results revealed that the critical velocity of Al particle at room temperature (RT) was 780 m s -1 , and the critical velocity decreased as particle temperature increased. On the basis of simulation results, mechanical properties such as bond strength of the coatings formed under various process conditions were evaluated and compared. These properties were discussed in terms of the processing-structure-property relationships.