ACTIVATION METHOD FOR ITEM FROM PASSIVE FERROUS AND NON-FERROUS METAL TILL CARBONISATION, NITRIDATION AND/OR NITRIDATION-CARBONISATION Russian patent published in 2014 - IPC C23C8/44 C23C8/48 C23C8/54 C23C8/64 C23C8/74 

FIELD: metallurgy.

SUBSTANCE: invention refers to the method of surface strengthening of items from stainless steel, nickel alloy, cobalt alloy or titanium-base material. A heater is provided having the first heating zone downstream of the second heating zone, gas inlet and gas outlet for gas passing through the heater, an item heating in the first heating zone to the first temperature in the range of 185-500°C, heating of at least one N/C connection containing nitrogen and carbon in the second heating zone to the second temperature of 135-450°C, which is lower than the first one, for formation of one or more gaseous substances. Mentioned connection has single, binary or triple link of carbon-nitrogen and is liquid or solid under the temperature of 25°C and pressure of 1 bar. Gas passes using carrier gas, which is nonoxidising for the item, for item contact with gaseous substances for the item activation, and item is continuously heated in this heater in the presence of gaseous substances to the temperature of nitridation-carbonisation, which is at least as high as the first temperature and is at least 500°C.

EFFECT: providing higher hardness and endurance strength of items treated by this method.

22 cl, 8 dwg, 8 ex