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In order to investigate the role of Au doping and diffusion-annealing duration on the mechanical properties of Bi–Pb–Sr–Ca–Cu–O, Bi1.8Pb0.35Sr1.9Ca2.1Cu3Oy superconductors were prepared by standard solid-state reaction methods. Doping of Bi-2223 was carried out by means of gold diffusion during sintering from an evaporated gold film on pellets. The effect of the diffusion-annealing duration on the mechanical and superconducting properties of these compounds was investigated using scanning electron microscopy, dc resistivity and hardness measurements. These measurements indicated that the Au doping and diffusion-annealing time increased the superconducting transition temperature, Vickers hardness, Young’s modulus, yield strength, fracture toughness values and improved the grain connectivity. The mechanical properties of the samples were found to be load dependent. In addition, we calculated the load independent hardness, Young’s modulus, yield strength and fracture toughness of the samples. These mechanical properties of the Au-doped samples were dependent on the diffusion-annealing time. Possible reasons for the observed improvements in the superconducting and mechanical properties due to Au diffusion are discussed.

We report measurements of temperature and magnetic field dependent magnetic susceptibility and electron paramagnetic resonance in the paramagnetic phase of CeB 6 . From calculations of the possible ground state level structure of the interacting 4 f electrons it is found that the fourfold degenerate ⌫ 8 is split into two doublets with equal g factors and an energy separation of the order of 30 K.

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