Abstract: Lead magnesium niobate (PMN) has many attractive features for precision submicron control. At room temperature hysteresis is less than 1%, thermal expansion is less than 1 ppm/$DGR@C, and the sensitivity is 375 ppm strain at 600 V/mm. There has been recent interest in using PMN actuators in applications near 0$DGR@C, which is near the Curie temperature of the PMN material. An investigation was conducted to obtain data on PMN:BA strain response and hysteresis at lower temperatures. Results of these experiments which were conducted to characterize the longitudinal and transverse field-induced strains at temperatures between $MIN@7$DGR@C to 24$DGR@C are provided for SELECT multilayer actuators and electroceramic plates. Measurements were made at 1 Hz both at constant maximum field (600 V/mm) as well as constant maximum strain (300 ppm for longitudinal; 140 ppm for transverse). Data shows that hysteresis and strain sensitivity to field increase monotonically as the temperature is decreased throughout the test range. Transverse strain is shown to track the longitudinal strain closely, within a simple scale factor. A comparison is made between constant field and constant strain hysteresis for both the longitudinal and transverse cases. Finally, data is presented which shows a factor of four reduction in hysteresis using passive charge control. !17
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