Superplastic alumina at temperatures below 1300 C using charge-compensating dopants
- Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Materials Science and Engineering
To achieve low-temperature superplasticity in alumina, the authors have introduced charge-compensating dopants, Ti{sup 4+} and Mn{sup 2+}, which jointly have a high solubility and significantly enhance the diffusion and deformation processes during sintering and forming. Zirconia as a second-phase pinning agent has also been incorporated to impart microstructural stability against static and dynamic grain growth. The superplastic alumina obtained can be shape-formed under biaxial tension to 100% engineering strain at temperatures below 1,300 C. Deformation characteristics of this alumina at temperatures from 1,200 to 1,400 C and at strain rates from 4 {times} 10{sup {minus}6} to 3 {times} 10{sup {minus}3}/s are described. The origin of enhanced kinetics is attributed to the formation and dissociation of dopant-defect complexes.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 203554
- Journal Information:
- Journal of the American Ceramic Society, Vol. 79, Issue 1; Other Information: PBD: Jan 1996
- Country of Publication:
- United States
- Language:
- English
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