摘要
This paper reviews the history of ZnO varistor,discribes its properties and recenttechnological status and forecasts its evolution.The future development trend is to produce the low-voltage high-energy multi-layer ZnO varistors.After the two additives are classified by their functions,the effect mechanism of Bi_2O_3 and TiO_2 additives are researched theoretically.TiO_2 will make ZnO graingrow bigger and V_ImA/mm be depressed down.Especially the colloid TiO_2 additive in the scale ofnanometer brings about a new method to realize the low voltage of ZnO varistor,which resolves theproblem of how to disturb nanometer powder evenly.Moreover the sintering temperature has prominenteffect on the electrical properties of ZnO varistors.Generally,the appropriate sintering temperature forlow-voltage ZnO varistor ceramics should not be more than 1 250℃.These provide an effective methodand rationale for studying low-voltage ZnO varistors.
This paper reviews the history of ZnO varistor,discribes its properties and recenttechnological status and forecasts its evolution.The future development trend is to produce the low-voltage high-energy multi-layer ZnO varistors.After the two additives are classified by their functions,the effect mechanism of Bi_2O_3 and TiO_2 additives are researched theoretically.TiO_2 will make ZnO graingrow bigger and V_ImA/mm be depressed down.Especially the colloid TiO_2 additive in the scale ofnanometer brings about a new method to realize the low voltage of ZnO varistor,which resolves theproblem of how to disturb nanometer powder evenly.Moreover the sintering temperature has prominenteffect on the electrical properties of ZnO varistors.Generally,the appropriate sintering temperature forlow-voltage ZnO varistor ceramics should not be more than 1 250℃.These provide an effective methodand rationale for studying low-voltage ZnO varistors.
