Publication Date:
2015-04-24
Description:
The temperature dependence of piezoelectric properties (direct piezoelectric coefficient d 33 , converse piezoelectric coefficient d 33 ( E = 0), strain S and electromechanical coupling coefficient k p ) for two niobate-based lead-free piezoceramics have been contrasted. 0.92(Na 0.5 K 0.5 )NbO 3 –0.02(Bi 1/2 Li 1/2 )TiO 3 –0.06BaZrO 3 (6BZ/2BLT/92NKN) has a morphotropic phase boundary (MPB) between rhombohedral and tetragonal at room temperature and 0.92(Na 0.5 K 0.5 )NbO 3 –0.03(Bi 1/2 Li 1/2 )TiO 3 –0.05BaZrO 3 (5BZ/3BLT/92NKN) features an MPB engineered to be located below room temperature. At 30°C, d 33 , d 33 ( E = 0), S (at 2 kV/mm), and k p are 252 pC/N, 230 pm/V, 0.069%, 0.51 for 5BZ/3BLT/92NKN; and 348 pC/N, 380 pm/V, 0.106%, 0.57 for 6BZ/2BLT/92NKN, respectively. With increasing temperature, the piezoelectric properties decrease. At 200°C, d 33 , d 33 ( E = 0), S (at 2 kV/mm), and k p are 170 pC/N, 160 pm/V, 0.059%, 0.36 for 5BZ/3BLT/92NKN; and 181 pC/N, 190 pm/V, 0.061%, 0.39 for 6BZ/2BLT/92NKN. It is found that the electromechanical coupling coefficient has a better temperature stability than the piezoelectric coefficient in the studied system due to a large temperature-dependent compliance change. The results demonstrate that engineering an MPB is highly effective in tailoring temperature stability of piezoceramics.
Print ISSN:
0002-7820
Electronic ISSN:
1551-2916
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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