METHOD FOR FORMING ANTI-CORROSIVE COATING ON THE SHAPED SURFACE OF A PRODUCT OF STRUCTURAL STEEL OF PERLITE CLASS Russian patent published in 2021 - IPC C23C26/00 B23K20/02 B23K20/227 C21D1/78 

FIELD: mechanical engineering.

SUBSTANCE: invention relates to mechanical engineering and can be used to create products from structural steel of the pearlite class, made with an anti-corrosion coating on the shaped surface and working in an aggressive environment. The method for forming an anticorrosive coating on an article with a shaped surface made of structural steel of a pearlite class includes preliminary production of a coating blank from a corrosion-resistant steel of austenitic class, which is placed on the surface of the article, and a welded joint is made between the coating blank and the article. A sealed shell is used as a coating blank, repeating the shape and relief of the product surface and equipped with a fitting made of the coating blank material and designed to be connected to the vacuum system. The sealed shell is made up of separate elements, which are placed on the sections of the product surface corresponding to them in shape and relief, and the said elements are connected to each other by hermetically sealed welds. After that, the internal volume between the sealed shell and the surface of the product is evacuated through the fitting and the hole in the fitting is sealed. The connection of a product with a sealed shell placed on its surface is carried out by diffusion welding under conditions of hot isostatic pressing with an exposure of 2-3 hours at a temperature of 1000-1160°С and a pressure of 150-170 MPa. When carrying out hot isostatic pressing at the cooling stage, when the high tempering temperature of 500-550°С is reached, the exposure is carried out for 2-3 hours.

EFFECT: improved quality of the anti-corrosion coating made on the shaped surface of the product made of structural steel of the pearlite class by ensuring the continuity of the anti-corrosion coating by eliminating defects in the form of lack of fusion and lack of penetration.

2 cl, 1 dwg