Growth, Structure And Performance Of PSN-PMN-PT Ferroelectric Crystal

Ferroelectric crystals are a kind of importance functional materials with superior properties, such as higher dielectric coefficient, higher piezoelectric coefficient, higher strain and higher energy storage density, et al. These materials have a promising application in medical imaging, communication and ultrasonic devices, et al. Due to low Curie temperature of PMN-PT and PZN-PT ferroelectric single crystals systems, PSN with high Curie temperature has been introduced to PMN-PT ferroelectric crystal to adjust its Curie temperature and electrical properties.The ferroelectric crystals of perovskite phase structure have been successfully grown by the temperature solutions method. The structure and properties of crystals have been studied. The biggest size of B component is up to9mm. The rhombohedral-tetragonal phase transition temperature is109℃higher than that of PMN-PT crystal and the Curie temperature is147.4℃, the piezoelectric coefficient is1210pC/N.The ferroelectric crystals of perovskite phase structure have been successfully grown by the Bridgman method. The structure and properties of crystals have been studied. The size of A component is up to (φ25mm×45mm. The piezoelectric coefficient is about2571pC/N, the Curie temperature is160℃higher than that of PMN-PT crystal. The size of A component is up to φ40mm×40mm. The piezoelectric coefficient is about962pC/N, the Curie temperature is126.7℃. The piezoelectric coefficient of C component is about151pC/N, the Curie temperature is170℃. The rhombohedral-tetragonal phase transition temperatures of three group crystals are all higher than those of PMN-PT crystal.B component crystals have been grown by different methods. The size of crystals by the Bridgman method is bigger, but the piezoelectric coefficient and Curie temperature are lower. Different component crystals have been grown by the same Bridgman method, the piezoelectric coefficient of A component is higher. The Curie temperature of C component was highest. Through two comparative methods, we can optained that the piezoelectric coefficients are different, because the orientation and composite are different. The Curie temperatures are different, because of composite segregation.