METHOD OF FORMING GRADIENT COATING WITH LASER DEPOSITION METHOD Russian patent published in 2019 - IPC C23C24/08 B23K26/342 C23C4/123 

FIELD: technological processes.

SUBSTANCE: invention relates to a method for forming a functional gradient coating by selective laser deposition. Powder material is supplied to the focus of laser radiation from at least two independently operated dispensers, in one of which there is a powder with low microhardness (less than HRC30) and high coefficient of thermal expansion (CTE) (more than 9 * 10^-6 C^-1), and in the other – with high microhardness (over HRC70) and low CTE (less than 6 * 10^-6 C^-1). At the beginning of the process a dispenser with plastic powder material with a high CTE is included and deposition of a high adhesive layer over the entire surface to be treated is produced with scanned laser beam, then a dispenser with a powder material with high microhardness and low CTE is included, so that when dispensers work simultaneously, the focus of the laser radiation will mix the powders of plastic material with the material with high microhardness with a gradual increase in the volume fraction of high-solid powder from 0 to 80 % and a decrease in the volume fraction of plastic powder from 100 to 20 % as each subsequent layer melts. Steel or alloys based on Ni, Cr, Co, Ti, etc. are used as a plastic material to create a high adhesive layer and nitrides, carbides, oxides, borides, or combinations thereof are used as the reinforcing agent. Fractional composition of powder materials is on average 60–160 microns.

EFFECT: as a result, coatings with enhanced adhesion and cohesive strength, wear resistance are obtained, which contributes to an increase in the service life of parts and products.

3 cl, 2 dwg, 2 ex