METHOD OF SANDWICHED COATING OBTAINMENT FOR CUTTING TOOL Russian patent published in 2015 - IPC C23C14/06 C23C14/26 B23B27/14 

FIELD: metallurgy.

SUBSTANCE: sandwiched coating is applied by vacuum plasma method. Lower layer of niobium carbide is applied first. Further, top layer of titanium, chrome and niobium compound nitride is applied at the following component ratio, wt %: titanium 79.0-85.0, chrome 9.0-11.0, niobium 6.0-10.0. Coating layers are applied by cathodes arranged in the same horizontal plane, where first cathode is composed of titanium and chrome, second cathode is made of niobium and opposed to the first cathode, and third cathode is made of titanium and niobium and positioned between first and second cathodes. Bottom layer is applied by the second cathode. Top layer is applied by the first and the third cathodes.

EFFECT: higher cutting tool efficiency.

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