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Information × Registration Number 0219U100450, 0117U004951 , R & D reports Title Development of the composition and technology of microplasma spraying of biocompatible cermet coatings with controlled structure popup.stage_title Head Borysov Iurii S., Доктор технічних наук Registration Date 13-02-2019 Organization E.O.Paton Elektric Welding Institute National Academy of scinces of Ukraine popup.description2  During fulfillment of work of stage II of the Project in 2018, it was established on the basis of calculation-theoretical analysis that during wire dispersion by microplasma jet, a condition for melt drop separation from the neutral wire tip is the velocity of microplasma jet in the range of Ti - 330 m/s, Zr - 350 m/s. This corresponds to the set plasma gas flow rate in the range of 100 - 300 l/h that is accompanied by formation of a turbulent mode of plasma Ar-jet outflow (Re = 3000 - 9000). It is found that under the conditions of microplasma spraying with wire materials at 1 mm diameter of jet forming nozzle at plasma gas flow rate within 100...300 l/h and up to 2.5 kW power of the plasma jet, the used wire diameter should be 0.3 mm for Ti and Zr, and the feed rate ensuring a stable dispersion process is 3.2 and 3.3 m/min for Ti and Zr, respectively. Investigation of the influence of different factors on the size of particles of wire melt dispersion products at microplasma wire straying revealed that the main methods to control the sprayed particle dimensions are changing the current value and plasma gas flow rate. Thus, the minimum average size of particles was achieved at dispersion of Ti and Zr wires in case of simultaneous application of maximum values of working parameters (142 ?m for Ti, 128 ?m for Zr). A combination of minimum values of current and plasma gas flow rate leads to formation of particles with maximum (or close to maximum) dimensions (342 ?m for Ti, 310 ?m for Zr). Product Description popup.authors popup.nrat_date 2020-04-02 Close