Superconductivity of annealed and consolidated amorphous YNi2B2C powders

Amorphous YNi2B2C powders have been produced by mechanical attrition. Super conductivity is absent in the amorphous state but recovers upon crystalliza tion. However, the superconducting transition temperature T-C is lower than that of the melted analogue. T-C can be increased by increasing the anneal ing temperature. High temperature compaction leads to dense bulk supercondu cting samples. T-C of these bulk samples can be optimised by annealing. Var iations in T-C are attributed to deviations from stoichiometry. Contaminati on of the powders with WC wear debris upon annealing may deteriorate the su perconducting properties.