Texture Evolution in Ni Substrate Prepared by Powder Metallurgy and Casting Methods

Abstract

Cube textured Ni substrate were fabricated for YBCO coated conductors from the initial specimens prepared by powder metallurgy (P/M) and casting and the effects of annealing temperature and reduction ratio on texture formation and microstructural evolutio were evaluated. The initial specimens were rolled by 98.6% and 99.2% reduction ratio and then annealed in the temperature range of 600°C to 1200°C. The microstructure and texture were evaluated by optical microscopy and X-ray pole-figure analysis. We observed that microstructure of the initial specimen varied with preparation methods.Texture analysis indicated that a strong cube texture formed for substrate made by P/M, and the degree of texture did not significantly vary with annealing temperature of 600°C~1100°C. On the other hand, the texture of substrate made by casting was more dependent on the annealing temperature and twin texture ({221}<221>) and several minor texture components started to form at 1000°C. In addition, the texture of substrate made by P/M was significantly dependent on the reduction ratio.