| 摘要 |
<p>PURPOSE:To recover constituting components with high efficiency in the stage of recovering W, Co, etc. which are the constituting components from coated superhard alloys by a molten zinc recovering method by heating the coated superhard alloys beforehand in H2, N2, CH4 atmospheres. CONSTITUTION:The superhard alloys coated with compds. such as carbides, nitrides, carbonitrides, oxides, carbooxides, oxynitrides, carboxynitrides or the like of metals in single or multiple layers are heated in an atmosphere of H2, N2 or CH4. Thereby, in the case of H2, oxides such as Al2O3 are reduced, and the coating layers are thoroughly removed or can be changed to fine powder-like Al2O. The TiC, TiN layers are made porous by N2 or CH4 and when these are charged into molten zinc, these react in contacting the Co, Ni in the superhard base materials. Further, in the case of double coatings such as Al2O3, TiC or the like, they are treated with H2 then N2, after which they are charged into molten zinc. If Co-Zn alloys, etc. are removed in this way, the WC, etc. of the hard layers are recovered.</p> |
