Corrective Effect of Average Grain Size on Grain Boundary Number of ZnO Varistors
The average intercept length and related corrective method are proposed to calculate the average grain boundary number. The average value of barrier voltage by direct measurement to single grain boundary is 3.3V in literatures, but from our prepared ZnO varistor samples, the value of the average barrier voltage by the average grain size is only 2.3 V. It is in the range from 3.24 to 3.38 V by the proposed method, which is very close to the direct measured value 3.3V of the single grain boundary. The introduced method to calculate average grain size has an obvious effect to correct the calculated barrier voltage to near the actual one by direct measurement to single grain boundary.
Wei Pan and Jianghong Gong
Y. P. Tu et al., "Corrective Effect of Average Grain Size on Grain Boundary Number of ZnO Varistors", Key Engineering Materials, Vols. 368-372, pp. 483-486, 2008