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Abstract

The production of compact molded bodies of rare-earth transition-metal boron carbide and boron nitride compounds configured so as to avoid a selective evaporation of individual components in the production process and enable an exact adjustment of the desired stoichiometry. The process is characterized in that a) a powder mixture with particles sizes from 1 to 250 .mu.m is produced, containing aa) at least one element from the group comprising Y, La, Ho, Dy, Er, Tm, Lu, Sc, ab) at least one element from the group comprising Ni, Cu, Co, Fe, Pd, Pt, ac) B and C or borides and carbides or nitrides and carbides or B and carbides or nitrides and carbon or mixtures of boron and carbon-containing solid solutions or mixtures of boron- and N-containing solid solutions; b) converting the powder mixture by mechanical alloying or intensive grinding under an atmosphere containing argon, nitrogen or carbon, into a secondary powder with an amorphous, glass-like structure, a completely nanocrystalline structure, or a mixture of an amorphous and nanocrystalline structure; c) heat-treating the secondary powder to form superconducting phases at formation temperatures below 1600.degree. C.; and d) compacting the secondary powder by pressure to form superconductor molded bodies at temperatures below the crystallization temperature of the amorphous phase or below the temperature where the superconducting phase transforms into a non-superconducting phase.

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First Claim