A new degradation analysis of ZnO-based varistors by AC impedance measurements is presented. From these measurements, which have been achieved on samples as a response to a small signal in the frequency range 10 -3 to 10 5 Hz, at room temperature, the distribution function of the relaxation time constant has been deduced. The heterogeneity factor beta characterizing the barriers constituting the ZnO-based varistors has been used as a measure of degradation. Our data reveal that the grain boundaries are not identical, in good agreement with the numerical/experimental current(I)-voltage(V) characteristics of various single-grain junctions.
No takes yet. Share an insight, caveat, or question.
Ai et al. (1991) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: