CUTTING TOOL WITH MULTILAYER COATING Russian patent published in 2003 - IPC

FIELD: tool manufacture, namely applying wear resistant coatings onto cutting tools. SUBSTANCE: cutting tool includes base of quick-cutting steel and wear resistant multilayer coating applied on base by ion-plasma process. Coating includes outer main coating of titanium nitride and inner adhesion underlayer containing element of material of outer main layer, namely titanium. Inner adhesion underlayer is made of nitride (of titanium, ferrum, nickel, chrome) with thickness 1.5 - 3 micrometers at next relation of metals in nitride (mass%): titanium, 72 - 94.5; ferrum, 4 - 20; nickel, 0.5 - 3; chrome, 1 - 5. Additional underlayer of titanium, ferrum, nickel and chrome is arranged between tool base and adhesion underlayer, it has thickness 1.5 micrometers at next relation of ingredients (mass%): titanium, 72 - 94.5; ferrum, 4 - 20; nickel, 0.5 -3; chrome, 1 - 5. Total thickness of coating consists 6 micrometers. EFFECT: lowered residual stresses, enhanced cohesion degree of coating and tool base, increased strength of cutting tool. 1 dwg, 1 tbl