Constricted hysteresis loops of unpolarized polycrystalline barium titanate — Energy loss, coercivity, and remanent polarization

A quantitative investigation was made of the rates of energy loss, coercivity, and remanent polarization in unpolarized ceramic barium titanate disks over the temperature range 0 to 75 C (degrees centigrade) as manifested in the rate of deconstriction of 60-cps (cycles per second) hysteresis loops. Empirical expressions were deduced which are first approximations for rather complicated rate processes. Constricted loops were synthesized by placing two oppositely oriented polarized disks together and applying a high a-c field. By way of explanation of constriction a model is given in which it is assumed that 180-degree domains are the principal cause.