Preparation and characterization of {100} < 001 > cube textured Ag substrates for in-plane oriented HTS tapes

A systematic study of texturing mechanisms in pure Ag is presented, the goa l being to obtain a cube textured {100}[001] tape that can be used as a sub strate for superconducting coated conductors. It is shown that a sharp cube texture can be produced after pre-heated deformation and recrystallization . Optimal parameters are detailed. 99.99% pure Ag powder is used as startin g material. Fine grained (15 mu m) Ag ingots are pre-heated at 100 degrees C before standard cold rolling. The effect of pre-heating an deformation te xture is to change the main texture from the brass orientation {110}[112] t o the Goss {110}[001] one. The presence of a copper-type texture with relat ively high valuer of the ODF (oriented distribution function) after the 100 degrees C pre-heated deformation can be understood as a slight increase; o f the stacking fault energy of Ag during the pre-heated deformation. The op timal annealing is achieved at 700 degrees C for 30 min in a primary vacuum . This leads to a sharp cube texture. The FWHM values of the three x-ray po le figures ate, at no more than 10 degrees, the smallest ever reported for cube textured Ag tapes. The Formation of cube texture is interpreted in ter ms of orientation nucleation and orientation growth theories that play a co mmon role during the texturing process. The stability of cube texture at hi gh temperature up to 900 degrees C: indicates that the tapes are suitable f or epitaxial growth of superconducting oxides.