FERROELECTRICS: THEIR ELECTRICAL BEHAVIOR DURING, AND SUBSEQUENT TO, IONIZING RADIATIONS

A study was made on certain ferroelectric materials which are among those used extensively in military applications, both in a polarized condition in such items as impact fuzes and in an unpolarized condition as capacitors. The transient voltages across a load produced by charge generated on the surface of various types of ferroelectric specimens during irradiation have been measured. These outputs were found to vary widely in amplitude and polarity even from specimens ostensibly alike i. e., from the same lot of a given manufacturer, and even from a single specimen pulsed repeatedly with gamma and neutron radiation. Pulses were found to vary from background levels to a high of 300 volts on a large specimen with a load of 10 to the 7th power ohms and radiation of 5.4 x 10 to the 14th power fast Pu neutrons and associated gammas. The maximum voltage possible is unknown, as are the factors causing the variation. Both polarized and unpolarized specimens showed outputs well above background transients. Some specimens were identical to those used in impact fuze applications and were in simulated housings which reproduce the mechanical environment of the device. Some fuze circuits in present use are discussed with reference to their use of ferroelectric materials and a calculation of the energy transferred by a voltage pulse to a load is presented.