METHOD AND DEVICE FOR COATING

The invention relates to metallurgy. The proposed method for coating of articles provides for introducing into a gas flow the powder of a material chosen from a group consisting of metals, alloys and their mechanical mixtures, or dielectrics, and having a particle size of 1 to about 50 mu m, in a quantity sufficient to ensure a mass flux density of the particles of 0.05 to 17 g/sec.cm , so as to form a gas-powder mixture which is directed on the surface of the article, the gas flow being given a supersonic speed and being formed into a supersonic jet of a desired profile providing for a speed of the powder particles in the gas-powder mixture of 300-1,200 m/sec. A device for implementation of the method comprises a doser-feeder (1) and, interconnected to each other, a bunker (2) for the powder, a means for dosing it consisting of a horizontally mounted drum (9) with recesses provided along a spiral line on its cylindrical surface (9'), a mixing chamber (3), a nozzle (4) intended for acceleration of the powder particles and connected to the mixing chamber (3), a compressed air source (5) connected to a means for feeding the compressed air to the mixing chamber (3), a flow regulator (11) for the powder particles mounted in relation to the cylindrical surface (9') of the drum (9) with a gap (12) ensuring the required mass flow of the powder, an intermediate nozzle (13) coupled with the mixing chamber (3) and connecting through its inlet pipe (8) to the means for feeding the compressed air, and a baffle (15) mounted on the bottom of the bunker (2) and in close proximity to the cylindrical surface (9') of the drum, the nozzle (4) for acceleration of the powder particles having a supersonic design and being provided with a profiled channel (18). L'invention concerne la métallurgie. Le procédé de revêtement d'articles consiste à introduire dans un flux de gas la poudre d'une matière choisie dans un groupe composé de métaux, d'alliages et de leurs mélanges mécaniques, ou diélectriques, et ayant une granulométrie comprise entre 1 et environ 50 mum en une quantité suffisante pour assurer la densité de flux massique des particules entre 0,05 et 17 g/sec.cm2, de manière à former un mélange gas/poudre que l'on oriente sur la surface de l'article, l'écoulement de gas étant accéléré à une vitesse supersonique et transformé en un jet supersonique d'un profil voulu assurant une vitesse des particules de poudre dans le mélange gas/poudre de 300 à 1200 m/sec. Un dispositif de