US 11,746,422 B2
Method of applying an intermetallic anticorrosion coating by thermal diffusion galvanization
Aleksey Nikolaevich Sonk, Moscow (RU); Igor′ Vladimirovich Petrov, pos.Kurkino (RU); and Igor′ Petrovich Yarema, Dolgoprudnyiy (RU)
Assigned to MAJORPACK INCORPORATED, Houston, TX (US)
Appl. No. 17/637,204
Filed by MAJORPACK INCORPORATED, Houston, TX (US)
PCT Filed Oct. 16, 2020, PCT No. PCT/RU2020/000544
§ 371(c)(1), (2) Date Feb. 22, 2022,
PCT Pub. No. WO2021/034223, PCT Pub. Date Feb. 25, 2021.
Claims priority of application No. RU2019126536 (RU), filed on Aug. 22, 2019.
Prior Publication US 2022/0290305 A1, Sep. 15, 2022
Int. Cl. C23C 24/00 (2006.01)
CPC C23C 24/00 (2013.01) 1 Claim
 
1. A method for applying a zinc coating to metallic articles by thermal diffusion galvanization, comprising:
loading articles to be treated into a hermetically sealed container;
loading a saturating zinc-containing mixture into the container;
filling a cavity of the container with an inert gas; and
heating;
wherein a two-component zinc mixture is loaded as the zinc-containing mixture;
wherein the two-component zinc mixture has a first component as a powder of acicular zinc having a size of 3-5 μm and loaded directly into the container, and a second component as a powder of spherical zinc having a size of 20-25 μm and loaded into a capsule having walls which disintegrate at a temperature of 400±20° C., the capsule being placed in the container concurrently with the articles to be treated;
wherein the first component is provided in an amount of 80% of a theoretical value of a weight required to cover a surface of the articles to be treated with an inner layer and 60% of a theoretical value of a weight required to cover the surface of the articles to be treated with an outer layer;
wherein a flux is loaded into the container, and an inert process gas and an activating agent for intensifying an adhesion process are supplied;
wherein the galvanization process is performed in two steps: first, heating to a temperature of 350-380° C. to form the inner layer of zinc due to an adhesion of the acicular zinc to the surface of the article to be treated, and then after heating a material of the capsule to the disintegration temperature of 400±20° C. and releasing the powder of spherical zinc to form the outer layer of the coating.