Sr:Nb stoichiometry and donor-doping with La were found to affect densification behavior and anisotropic grain growth in Sr2Nb2O7 ceramics. La-doping improved the high temperature a.c. resistivity, but inhibits grain growth by grain boundary pinning. The presence of excess Nb was found to promote anisotropic grain growth by forming a liquid at the grain boundaries in both undoped and doped Sr2Nb2O7. Anisotropic grain growth in La-doped Sr2Nb2O7 can be controlled by incorporating large template particles in a Nb-rich matrix. High sintered densities (approx. 98% of theoretical) were achieved in both undoped and La-doped samples.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering