The invention belongs to the field of
machining cutting tools, and relates to an AlNbCN multielement gradient
composite coating tool and a preparing method thereof. The
coating tool sequentially comprises a tool base body, a Ti
transition layer, an AlNbC
transition layer and an AlNbCN multielement gradient
composite coating with the
nitrogen content gradually changing in a gradient manner from interior to exterior, and the
coating tool is prepared in a middle-frequency magnetron
sputtering and arc plating
composite coating method. According to the AlNbCN ultrahard carbohydrates and nitrogenous compound
coating, due to the fact that the
Al element and the Nb element are added in the coating at the same time, and the content of the
nitrogen which is the structure component of the coating gradually changes in a gradient manner, thecutting
machining performance of the tool can be improved. The AlNbCN multielement gradient composite coating tool has very high
hardness and strength, low
surface friction coefficient, good high-temperature oxidization preventing performance and excellent friction abrasion characters. In the
cutting process, tool
surface friction and cuttings bonding can be reduced through the tool, the
cutting force and the cutting temperature can be reduced by 45% or above, the
heat stability of the coating tool is improved by 65% or above, the service life of the tool is prolonged by 60% or above, and durability of the tool is improved by 60% or above.