METHOD OF PREPARATION OF HARD-ALLOY MIXTURES FROM USED HARD ALLOYS Russian patent published in 2000 - IPC

FIELD: powdery metallurgy, particularly, processing of hard-alloy wastes. SUBSTANCE: method includes annealing of hard-alloy scrap in protective atmosphere or vacuum, crushing, milling to 40 mcm and finer fraction. In so doing, scrap before annealing is sorted in lot by chemical composition and weight, and surface impurities are removed. Annealing temperature for each lot is determined depending on cobalt content by formula t=K+B , where t is annealing temperature, C; K is coefficient accounting for technical condition of furnace and equalling 1375-1740; B is coefficient accounting for weight of scrap for one-time annealing equalling 2900- 3080; [Co] is cobalt concentration. EFFECT: provided preparation of commercial mixtures suitable for manufacture of high-quality hard-alloy products. 4 cl, 2 dwg