Structural and superconducting properties of mechanically alloyed Y-Pd1-xTMx-B-C (TM = Ni, Pt)

Among the borocarbides the highest T-c of about 23K occurs in the system Y- Pd-B-C. Pseudo-quaternary Y(Pd1-xNix)(2)B2C and Y(Pd1-xPtx)(2)B2C samples w ere prepared by mechanical alloying followed by a thermal treatment. For Y( Pd1-xNix)(2)B2C superconductivity was only detected for Ni contents x > 0.3 after annealing. Pt stabilizes the formation of the tetragonal superconduc ting phase leading to an almost single-phase X-ray diffraction pattern and to T-c near 15K for Y(Pd0.8Pt0.2)(2)B2C after annealing at 1273 K. (C) 2000 Published by Elsevier Science B.V. All rights reserved.