METHOD OF PRODUCING SANDWICHED COATING FOR CUTTING TOOL Russian patent published in 2017 - IPC C23C14/22 B23B27/14 

FIELD: metallurgy.

SUBSTANCE: multi-layer coating is applied by vacuum plasma method. First, a lower layer of zirconium nitride is applied. Then the top layer of nitride of titanium, silicon and niobium is applied at the following ratio of components, wt %: titanium 88.6-93.0, silicon 1.0-1.4 niobium 6.0-10.0. Coating layers are applied by three cathodes arranged horizontally in one plane. The first cathode is made of titanium and silicon alloy, the second cathode is made of zirconium and opposed to the first cathode, while the third cathode is composed of titanium and niobium and positioned between the first and the second cathodes. The bottom layer is applied with the help of second cathode while top layer is applied by the first and the third cathodes.

EFFECT: higher efficiency of the cutting tool.

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