二乙胺法制备含多种添加剂的ZnO粉体与变阻器陶瓷的研究

Preparation of Multicomponent Modified ZnO Varistor by Diethylamine Method

本文采用二乙胺化学制备方法研制了如下6种成份组成的 ZnO 粉料:97mol%ZnO+0.5mol%Bi_2O_3+0.5mol%CO_2O_3+0.5mol%Cr_2O_3+1.0mol%Sb_2O_3+0.5mol%MnO_(?)。测量了粉体的粒度分布,粒径<1μm 的粉体占70～80%,其平均粒径为0.5μm 左右。测量瓷体的烧结密度和电物理特性-α值,并用SEM 对粉体和陶瓷进行观察。实验结果表明:本法可获得电物理特性优良、成份均匀的粉料,瓷体的烧结密度较高(理论密度的97%),晶粒较细且均匀。实验中还发现:化学制备 ZnO 陶瓷无焦绿石相呈现及消失。表明了制备方法不同,材料的相变化亦不同。

ZnO powders with 97mol% ZnO+0.5mol% Bi_2O_3+0.5mol% Co_2O_3+0.5mol%Cr_2O_3+1mol% Sb_2O_3+0.5mol% MnO_2 were prepared by the diethylamine method.Particle size distribution of the powders was determined by Stokes′law sedimenta-tion technique.The density of sintered ceramics and its electrophysical characteri-stics were examined.SEM observation for the powders and ceramics was alsocarried out.The results show that the portion about 1μm amounts to 70-80% andthe average particle size is about 0.5μm.Homogeneous powders in composition andhigh dense ceramics (97% of theoretical density) with small and uniform grainsize,and excellent electrophysical a value can be obtained by the diethylaminemethod.It is also showed that the pyrochlore type phase does not appear duringthe sintering process,by using such manufacturing method.This means that diffe-rent phase transitions may be present in the same ceramic material by using thedifferent manufacturing methods.