Sol-gel coating of YBa2Cu3O7-δ powders for enhanced critical current

The ability to properly control grain orientation within the microstructure of YBa2Cu3O7-δ superconducting ceramics is thought to allow improvement in critical current densities. This investigation examined the use of a sol-gel process for the addition of liquid phase sintering aids to enhance grain orientation as well as to introduce flux pinning precipitates. Silicon and titanium containing additives were incorporated via sol-gel coating of YBa2Cu3O7-δ powders. Hot forging was employed for improved grain texturing during sintering. XRD and SEM analysis was used to evaluate the phase composition and microstructure at various stages of processing. Magnetic ac susceptibility measurements were conducted, along with transport current density, and correlated to the resultant microstructures