Rolling and Recrystallization Textures in a Ni Substrate with High Reduction for YBCO Films

Rolling and recrystallization textures in a Ni substrate deformed to 80%∼95% reduction have been investigated systematically in the processing of a high quality cube textured substrate for YBCO thick films. The starting high purity (99. 99%) Ni sheet was deformed at room temperature to 80%, 89%, 93% and 95% reduction. The sample with 95% reduction was heat treated at 750°C, 800°C, 850°C, 900°C, 950°C and 1 000°C for 5 h. The formation and evolution of rolling and recrystallization textures were investigated by X ray pole figure measurement and the results quantified in terms of the orientation distribution function (ODF). The results show that the C{112}〈111〉and S(123)〈634〉orientation densities increase with increasing reductions, the cube texture volume fraction increases and the φ scan full width at half maximum (FWHM) decreases with increasing heat-treatment temperature. The cube texture deviates from its regular position in the range of 12° to 13° at lower heat treatment temperature. As the heat-treatment temperature increase towards 1 000°C, the deviation from regular position decreases, and a sharp cube texture develops.