An improved kinetic spray
system and a method for using the same in a high speed manufacturing environment are disclosed. The improved kinetic
spray nozzle system comprises: a gas /
powder exchange chamber connected to a first end of a
powder /
gas conditioning chamber having a length along a longitudinal axis of equal to or greater than 20 millimeters; a converging diverging
supersonic nozzle, the
supersonic nozzle having a converging section separated from a diverging section by a
throat, the diverging section comprising a first portion and a second portion, with the first portion having a cross-sectional area that increases along a length of the first portion and with the second portion having a substantially constant cross-sectional area along a length of the second portion; and the converging section connected to a second end of the
powder /
gas conditioning chamber opposite the first end. The method includes: use of the disclosed
nozzle system with the addition of hard particles that permit maximum enhancement of
particle temperature while not permitting clogging of the
nozzle; use of controlled particle feed rates to match the desired very high
traverse speeds; and use of pre-heating of the substrate to clean it an to enhance particle bonding. With the disclosed
nozzle system coupled with the disclosed methods one can apply kinetic spray coatings at
traverse speeds of over 200 centimeters per second with a deposition efficiency of over 80 percent.