METHOD OF PRODUCING SANDWICHED COATING FOR CUTTING TOOL Russian patent published in 2013 - IPC C23C14/24 C23C14/06 B23B27/14 

FIELD: metallurgy.

SUBSTANCE: applied is lower layer of titanium, niobium and zirconium nitrides at the following ratio of components in wt %: titanium - 76.0-84.0, niobium - 4.0-8.0, zirconium - 12.0-16.0. Then mid layer of carbonitride of titanium, niobium and zirconium is applied at the following ratio of components in wt %: titanium - 76.0-84.0, niobium - 4.0-8.0, zirconium - 12.0-16.0. Then top layer of carbonitride of titanium, niobium and zirconium is applied at the following ratio of components in wt %: titanium - 88.0-94.0, niobium - 6.0-12.0. Coating layers are applied horizontally in one plane by three cathodes. First and second cathodes are made of titanium and niobium alloys and arranged in opposition while third cathode is made of titanium and zirconium and arranged there between. Lower and mid layers are applied by three cathodes while upper layer is applied by first and second cathodes.

EFFECT: higher cutting efficiency.

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