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

FIELD: metallurgy.

SUBSTANCE: vacuum plasma sandwiched coating is applied. First, applied is lower layer of titanium, niobium and silicon nitrides at the following ratio of components in wt %: titanium - 91.15-95.35, niobium - 4.0-8.0, silicon - 0.65-0.85. Then mid layer of carbonitride of titanium, niobium and silicon is applied at the following ratio of components, wt %: titanium - 91.15-95.35, niobium - 4.0-8.0, silicon - 0.65-0.85. Then tap layer of carbonitride of titanium and niobium is applied at the following ratio of components, wt %: titanium - 88.0-94.0, niobium - 6.0-12.0. Coating layers are applied by three cathodes located horizontally in one plane First and second compound opposed cathodes of titanium and niobium 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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