Preparation and preliminary mechanical characterization of sintered Bi2Sr2CaCu2O8 and SnO2 based composites.
Résumé
The preparation of the composites by sintering of pressed pellets is described. They were characterized by means of the Brazilian test, which leads in a first step to a determination of the tensile strength. The evolution of this mechanical property with composition displays a sudden increase for a volume fraction of the superconducting ceramics Phi(Bi-2212) approximate to 0.25, close to that of the percolation threshold previously observed in the case of the conductive and superconductive properties. This similarity can be explained by the existence of the same 3D infinite cluster of continuous polycrystalline lines.