| Autor: |
Brajer, E. J., Jaffe, Hans, Kulcsar, Frank |
| Zdroj: |
Journal of the Acoustical Society of America; 1952, Vol. 24 Issue 1, p117-117, 1p |
| Abstrakt: |
We have found that the second transition point occurring near 10°C in barium titanate (BaTiO3) is raised by the incorporation of zirconium oxide at the rate of about 5°C per mole percent ZrO2. This makes it practical to utilize the high values of piezoelectric voltage output found in polarized barium titanate ceramic at temperatures below the second transition. The Curie point is lowered about 3°C per mole ZrO2. Barium zirconate (BaZrO2) addition causes the same shift in both transition points, but does not give as high a voltage output coefficient as ZrO2. Stannic oxide and barium stannate cause a larger downward shift of the Curie point but a smaller upward shift of the second transition than zirconium oxide. Other additions, including lead titanate, lower the second transition point. This effect is desirable for piezoelectric ceramics where large variations of capacitance with temperature in the operating range are to be avoided. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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