Parameters of the Gas-Powder Supersonic Jet in Cold Spraying Using a Mask

Behavior of an axisymmetric cold spray supersonic gas-particle jet passing through an axisymmetric aperture having a diameter smaller than the jet dimensions is considered. The particular case studied in the paper is the interaction between a supersonic jet delivered by a nozzle with a 7.8 mm exit diameter and a solid plate with a 3 mm aperture. The gas and aluminum particle parameters after passing through the aperture are experimentally and numerically studied. Under conditions used in this study, the decelerating influence of the aperture on the aluminum particle velocity is found negligible for spray distances less than 40 mm.