| Abstract: |
Superior characteristics of the cold sprayed coating have led to many high-tech applications. Till recently, all these applications were carried out using stationary systems only, while some applications such as in-situ repair of aircraft body/engine parts, require a portable system. Recently a Portable High Pressure Cold Spray System called KINETIKS 2000 has been developed. This system is capable of 400 C/20 bars nitrogen/helium jet, and produces dense coatings with clean interfaces of many materials.
In order to establish the suitability of this process for producing aluminum alloy coatings for aerospace and other high tech industries, a series of experiments were carried out to produce various aluminum alloy (CP-Al, HP-Al, 7005 Al) coatings over many substrate materials (2024 Al, 7005 Al, 4041 Steel, ZE41A Mg). Produced coatings were characterized using microstructure, bond strength, bend test, corrosion studies, etc. Microstructural study showed that dense coatings with about 2-4% porosity values were produced with clean and well bonded interfaces. Bond strength of these coatings varied in the range of 20-35 MPa, depending on the coating and substrate materials. Bent test results showed that the coatings have adequate cohesive and adhesive strengths, and could withstand severe strain conditions. Salt fag corrosion studies (ASTM B 117) using both scribed and unscribed specimens showed that the coatings impart corrosion resistance to the substrates, but improvements are required for achieving better surface protection.
In summary, results to this date have shown the potentials of this process. Studies are continuing to further improve the coating properties and standardize the coating procedure.
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