Bi2O3 vaporization from ZnO-based varistors

摘要: Abstract Bi 2 O 3 -doped ZnO ceramic varistors are usually sintered at temperatures near to 1200 °C in the presence of a Bi-rich liquid phase, which is partially vaporized during sintering process. Volatilization bismuth oxide depends on total surface area direct contact reaction atmosphere and this turn related area/volume ratio compact. This loss has significant role development varistor microstructure more specifically grain growth, strongly enhanced by should be particularly affected. In present paper, X-ray fluorescence analysis performed describe vaporization profile as function distance outer surface, taking into account its influence microstructural evolution.