Takeshige Hamatsuki

Internal electrode piezoelectric ceramic actuator

Abstract A piezoelectric ceramic actuator element with multilayer internal electrodes has been investigated. It was fabricated by multilayer ceramic capacitor techniques. An individual internal electrode has the same area as the element cross section area. It has no piezoelectric inactive part, so that it shows original strain/field characteristics in the material. It can be driven by a relatively low votlage (< 200V) and has a semi-permanent life under successive voltage pulse application. Typical properties of the element using 0·65Pb(Mg1/3Nb2/3)O3-0·35PbTiO3 ceramics are 8·7 × 10−4 strain, over 3·5 × 107 N/m2 force, within 100 μsec response time and 70% electromechanical couplig factor driven by 1 × 106 V/m field.

Internal Electrode Piezoelectric Ceramic Actuator

An internal electrode multilayer piezoelectric ceramic actuator element has been investigated. An individual internal electrode has the same area as the element cross section area. It has no piezoelectric inactive part, so that it shows strain/field characteristics similar to plain piezoelectric ceramics. It can be driven by a relatively low voltage (200 V) and has a semipermanent life under a successive voltage pulse application. Typical properties of the element using 0.65Pb(Mg1/3Nb2/3)O3-0.35PbTiO3 ceramics are 8.7×10-4 strain, over 3.5×107 N/m2 stress and within 100 µsec response time driven by 1×106 V/m field.

Space Simulation Tests of the Highly Stable Crystal Oscillators for Space Use

The artificial satellite-borne 5. 6 MHz quartz crystal oscillators for tracking using the Doppler effect were developed and tested in the space simulation chambers in which the environmental temperature was changed cyclically from 0°C to 40°C over 90 minutes period and the environmental pressure was kept less than 5×10-6 Torr. In order to decrease the temperature change of the crystals, the oscillators are provided with the passive thermal control device, and the temperature amplitude reduction rate by it was measured to be about 1/500. This corresponds to the frequency change of 5×10-9 per 10 minutes, which met the design requirement. This report presents the results of the space simulation test, and discussed the design criteria of this type of the oscillators.