TOOL STRENGTHENING METHOD Russian patent published in 2007 - IPC C23C28/00 C23C14/48 

FIELD: machine engineering, namely tool strengthening method, possibly for increasing operation resource of metal cutting tools, for example of cold forging punches.

SUBSTANCE: method comprises steps of saturating working surface of tool with nitrogen by depth 30 - 40 micrometers before applying multiple-layer coating for performing compensation of difference of thermal-physical-mechanical properties of coating and tool materials; applying onto nitrogen-saturated surface mutually alternating intermediate and compensating layers. Hardness of next intermediate layer is higher than that of previous one. Intermediate layers provide gradual change of hardness from substrate to surface of coating and therefore they provide increased impact viscosity. Compensating layers made of pure titanium or chrome provide bonding between layers. After applying each layer, ion polishing is realized. Last surface layer is made of plastic material used for running and concealing micro-cracks of wear-resistant layer of coating.

EFFECT: enhanced resource of tool subjected to dynamic loads at operation.

1 dwg