Study on Piezoelectric Effect and Magnetic Properties of Tourmalines

Abstract

The piezoelectric effect was determined and the magnetization testing of diverse tourmalines was carried out in this paper. The results show that static voltage on both ends of tourmaline crystal enhances gradually with pressure enhancing, but there is no linear function between each other. At the very time when crystal breaks, the static voltage can reach a maximum value. The direction of the static voltage is reverse when giving and losing pressure. The performances of piezoelectric strength are as follows: Elbaite>Schorl>Dravite. The piezoelectricity on both ends of tourmaline crystal is stronger than that on cylinder surface, which is 3 ~ 4 times of the cylindrical surface. The piezoelectric strength of tourmaline crystal has nothing to do with its crystal volume but has something to do with the crystal surface streak. The performance is that the more limpid of the crystal surface streak is, the more obvious of the piezoelectric effect is. The overall tourmaline magnetization is weak. Magnetic susceptibility is a linear function of the refractive index and Fe-contents. Magnetic susceptibility of Schorl is greater than that of Elbaite. Saturation magnetization and remanence magnetic of Schorl are greater perpendicular to than parallel to C axis.