To reduce the transportation cost, to improve the quality and to increase the reutilization value by heating a spent sintered hard alloy (WC-Co base) part in a tin metal bath, allowing only Co to react with tin to take out as a metallic compound and to make the sintered hard alloy part brittle and easily pulverizing WC.

This sintered hard alloy to be broken is charged into tin heated to 1,050°C and melted in a small sized simple quenching furnace and is held for a fixed time. The tin bathing time is different with the size of the alloy part and the impregnating speed of tin from the surface of the part to the center is fixed by the temp. condition. Next, the part is taken out from the bath and is cleaned while being stirred in concentrated hydrochloric acid for about 1 hr and as a result, the compound of tin with Co and excessively impregnated tin are washed out and the shape is broken. After the filtration and recovery thereof, the WC fine powder having 1.0-4.0 μm particle diameter, which is in nearly the same state as that before sintered, is obtained by pulverizing by a stamp mill or the like.