As part of the ceramic activity the research in the following areas is being pursued:
- Transparent Ceramics
- Relaxor Ferroelectrics
- Multiferroics
- Major facilities
Transparent Ceramics
Monolithic growth of free-standing ZnS was carried out using sub-atmospheric pressure chemical vapour deposition (CVD) (Figure 1). Transparent Nd and Yb-doped PLZT have been fabricated using hot-press sintering (Figure 2). Currently development of Nd-YAG and Yb-Y2O3 ceramics are being pursued.
  Free-standing transparent ZnS blanks and dome |
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 Nd-PLZT ceramics and UV-Vis-NIR transmission |
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 Yb-PLZT ceramics and UV-Vis-NIR transmissione |
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Relaxor Ferroelectrics
The mechanism of relaxation and relaxor to normal-ferroelectric transformation in (1-x)PMN-xPZ solid solutions has been investigated. A cross-over in the composition range 0.42 < x < 0.46 was observed. The piezoelectric (d33) and electromechanical (k31) coefficients were maximum in the vicinity of the cross-over region.
Shape-memory strain in thin bars of PMN-PT ceramic for compositions near its morphotropic phase-boundary has been observed. The maximum pseudo-plastic strain measured was ~ 0.3% in 65/35 PMN-PT and was found to be inversely related to the relaxor characteristic parameter “γ†(Figure 2). These studies showed that the pseudo-plastic strain depends on the composition, La3+ ions doping concentration, temperature, pressure, and thermal history.