MULTI-LAYER COMPOSITE COATING ON STEEL PRODUCED BY METHOD OF CHEMICAL DEPOSITION Russian patent published in 2015 - IPC C23C18/32 B32B15/00 

FIELD: metallurgy.

SUBSTANCE: coating contains at least six components, i.e. nickel, cobalt, phosphorous, chemical compounds of nickel with phosphorous - Ni₃P, Ni₅P₂, Ni₂P, and comprises several alternating layers, at that odd layers are solid phosphorous solution in nickel, and even layers are solid solution of phosphorous in cobalt, at that interrelationship of the alternating layers is ensured due to jointing of next layer matrix with the previous layer matrix. In the odd layers of the coating the particles of nickel, phosphorous, chemical compounds Ni₃P, Ni₅P₂, Ni₂P have size within range from 40 to 1000 nm. In even layers of the coating the cobalt and phosphorous particles have size from 300 to 5100 nm.

EFFECT: multi-layer composite coatings have high microhardness and corrosion-resistance.

4 cl, 1 dwg, 2 tbl, 4 ex