In a cold spray technique(CS),which used for making dense and thick metallic coatings,the deposition mechanism of fine solid particles is the most important research target.However,it is difficult to experimentally evaluate the deposition mechanism due to numerous impingements of very fine particles with various size and shape.In this study,in order to figure out the deposition mechanism,single particle shot system(SPSS)was developed.In this system,single spherical particle with 1mm diameter can be impinged on a substrate.The structure of the SPSS is based on normal single-stage light gas gun.The remarkable points of the SPSS are original separation system of particle from particle holder,and launch system with solenoid valve.These contributed to downsizing of total system,short experimental time,and low gas consumption.Particle velocities can be controlled by gas pressure of nitrogen or helium gas.And maximum particle velocity of 600m/s,which was accurately measured by two lasers,was achieved.Using the SPSS,the deposition behaviors and critical velocities of 1 mm aluminum particles impinged on five substrate materials could be appropriately evaluated.These indicate the effectiveness of the SPSS for evaluation of particle deposition mechanism.

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