Powder metallurgy has been used by a number of
workers to fabricate superconductor -metal composites.'"
This method involves mixing superconductor powder and
metal powder and then sintering" or mixing metallic Y,
Ba, Cu,and Ag and oxidizing. The main drawback of this
method includes the following;
(a) The metal content is limited to 50 vol.% or below
in order to have a continuous superconducting path in the
composite. This limits the ductility of the composite.
(b) The choice of metal is limited to metals that are
stable at the sintering temperature in oxygen and do not
react with the superconductor at the sintering temperature
(typically 950 C for YBa2Cti30,_A).
Yet another method that has been used in forming
a superconductor -metal composite involves (i) Packing a
superconductor powder in a metal tube, (ii) drawing the
tube to a smaller diameter, and (iii) sintering." The main
drawback of this technique is that the choice of metal is
limited to metals that are stable at the high sintering tem-
perature required by the superconductor