SINTERING PROCESS AND MECHANICAL-PROPERTIES IN STEEL SUPERCONDUCTOR GRANULAR COMPOSITES/

A study of two-phase composite pellets obtained from powders of stainl ess steel and of a bismuth cuprate superconductor (Bi2-xPbxSr2Ca2Cu3O1 0-x) has been carried out, using scanning electron microscopy, magneti c field expulsion analyses and elastic modulus measurements. Each comp osite sample is defined by its initial volume fraction, its sintering temperature and sintering duration. The magnetic responses of the comp osites are determined from levitation experiments. The Young modulus E and the elastic limit R-c are measured from compression experiments. A correlation between the scanning electron images, the levitation for ces F-lev and the elastic properties is established. When the volume f raction of steel or the sintering temperature increase, the Young modu lus E and the elastic limit R-c both decrease. When the sintering dura tion increases, the elastic properties are improved. The role of pores and of the liquid phase formed during the sintering process is discus sed. (C) 1998 Elsevier Science B.V. All rights reserved.