Scale-Up of a Batch-Type Chemical Powder Preparation Process for High Field Varistor Fabrication

摘要

A batch-type chemical preparation process for the fabrication of high field varistor powders was scaled-up from a laboratory scale to a batch size (1 kg) deemed suitable for technology transfer to an appropriate manufacturing agency. Process development activities concerning batch preparation and reproducibility, impurity effects on varistor properties, electrical property degradation, and other scale-up problems were investigated. Detailed descriptions of the specific problems encountered and the resulting solutions are documented. A summary of the 1 kg inter-batch reproducibility with respect to both powder characteristics and sintered varistor properties is presented. In-depth process documentation is supplied in the appendices of this report. 40 refs., 15 figs., 12 tabs. (ERA citation 13:022337)