Monosize alloy droplets are produced by controlled capillary jet break-up, a droplet generating process, also used in ink jet printing technology. With Rayleigh instability controlled through the decoupled process parameters of jet diameter, mass flowrate and perturbation frequency, monosize droplets of desired diameter can be generated at high rates with essentially full yield. The uniform size of droplets assures nearly identical solidification paths for all the droplets generated under fixed process conditions. This permits precise prediction of the motion and thermal and solidification behaviours of the droplets through rigorous process and metallurgical modelling, which is applicable to industrial thermal spray processes as well. Uniform droplets can be in-flight solidified or deposited on a substrate to produce various forms of materials with novel rapid solidification microstructures. Areas of industrial applications are discussed.
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