METHOD OF PREPARING SURFACE OF CARBON AND LOW-ALLOY STEELS FOR APPLYING POLYMER COATINGS Russian patent published in 2024 - IPC B23K26/00 

FIELD: various technological processes.

SUBSTANCE: invention relates to surface preparation of steel articles made from carbon and low-alloy steels for application of various functional paint coatings based on polymer materials in order to increase their adhesion to the steel surface of the article after two-step treatment by exposing the surface of the article to laser radiation of a fibre nanosecond laser with further cold phosphating of the surface. Advantage of the method consists in the fact that complex two-stage processing of steel surface allows obtaining uniform ordered profile of surface without sharp drops and "pockets", which can affect quality of adhesion of finish coating. On the other hand, due to the "cold" phosphating operation, a developed microcrystalline surface is formed, which increases contact with the finish coating and provides additional anticorrosion protection. Besides, due to combination of operations it is possible to achieve a pronounced value of roughness of 6.6 mcm, which also has a positive effect on growth of adhesion strength.

EFFECT: improved adhesion properties of carbon and low-alloyed steels surface.

1 cl, 2 dwg, 2 tbl, 16 ex