High-power properties of crystal-oriented (Sr,Ca)_2NaNb_5O_(15) piezoelectric ceramics and their application to ultrasonic motors

摘要

The high-power properties of c-axis crystal-oriented (Sr, Ca)(2)NaNb5O15 (SCNN) plate were investigated under large-amplitude vibration using an electrical transient response. The ultrasonic motor of a 31-vibration mode using the crystal-oriented SCNN plate was fabricated and evaluated. The quality factor of crystal-oriented SCNN plate increased to about five times higher of randomly oriented SCNN and (Bi, Na, Ba)(Ti, Mn)O-3 disks. The mechanical nonlinearity behavior was not observed and the temperature dependences of the quality factor and the equivalent stiffness decreased ignorable. The high-power properties were considered to originate from decreasing strictly the internal stress induced from crystal anisotropy by the crystal-oriented morphology. The motor showed the revolution speed 100 rpm in torque from 150 mu N m to 900 mu N m, the output power 7.5 mW, efficiency 3.5% at 657 mu N m and 109 rpm. The output power was about twotimes higher in the previous study. The performance reflects the superior high-power properties of crystal-oriented SCNN ceramics. (C) 2019 The Japan Society of Applied Physics