Cold Spray Process ~ Overview and Application Trends ~
In Cold Spray method, a coating is formed by exposing a substrate to high velocity solid-phase particles, which have been accelerated by supersonic gas flow at a temperature much lower than the melting or softening temperature of the feedstock. Therefore, the nozzle geometry is important with regard to the cold spray method. This Cold Spray process is an exciting new spray technology that has the potential to overcome limitations of more traditional thermal spray processes for some important commercial applications. With this emerging technology, it is possible for the first time to rapidly deposit thin or very thick layers (mm to cm+) of a wide range of metals, and even some composite materials, without melting or vaporization, at or near room temperature, in an ambient air environment. Some potential areas of interest include: corrosion protection, wear reduction, highly conductive coatings (electrical or thermal), metal/glass or metal/ceramic joints (with less residual stress), ceramic/metal or graded metal/metal composites, thick deposits (mm to several cm range), reclamation of worn or mis-machined parts, metallization of glass or ceramics. The applications of Cold Spray can be examined in the field of an automobile and a rocket engine.
S.-G. Kang and T. Kobayashi
K. Sakaki, "Cold Spray Process ~ Overview and Application Trends ~", Materials Science Forum, Vols. 449-452, pp. 1305-1308, 2004