An improved press forging technique has yielded ceramic Ba2YCu3Ox with a very high degree of orientation and mechanical integrity. The as‐forged samples are dense and tetragonal, and have an oxygen content of ≊6.3. By a partial oxidation of the samples, a superconducting skin 20–100 μm thick is formed on the outer surface. Transport measurements on this skin show a Jc >3000 A/cm2 with an improved field dependence as compared with randomly oriented samples. The restriction of oxidation to the thin outer skin has reduced the microcracking which accompanies the oxidation of tetragonal Ba2YCu3Ox.

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