Zinc oxide linear resistance medium and its preparation method

Abstract

The invented linear resistance medium of zine oxide and its preparation method includes following steps. With the weight constituent: zinc oxide 60-90%, magnesia 1-10%, alumina 1-20%, multielement additive 3-15% of 3-4 classes among titanium oxide, calcium oxide, mullite and spinel being mixed and ball milled, the granules are made by spraying and isostatic compaction. Then, after the granules being burned in the electrothermal tunnel kiln at 1250-1350 deg.C, the ceramics resistance medium is made. The ceramics resistance medium possesses the following characters: resistivity 1-10 to the power 4 ohm.cm, resistance power 800 joule / cm3, resistance temperature coefficient 1x10 to the power -3 ohm / deg etc. The invented medium can be widely used as the switch or resistor, the grounding resistor, the absorbing resistor and the power termination resistor.

Description

technical field [0001] The invention relates to a linear resistor medium and a preparation method thereof. Background technique [0002] The earlier ceramic linear resistors were made of alumina and clay as the base material doped with carbon powder, because of their low sintering density and energy tolerance of less than 300 joules / cm 3 , and the resistance value drifts nearly 10% at 20-250°C, so it cannot meet the requirements for the use of high-energy absorbing resistor devices in power transmission and distribution systems; Chinese patent No. 96123503.9 discloses a zinc oxide ceramic linear resistor and its manufacturing method. The new ceramic resistors prepared by this method have the advantages of good temperature characteristics and high surge resistance, but the method described is a laboratory research technology and is not suitable for modern industrial production. The energy tolerance of its products is 680 joules / cm 3 , not exceeding 800 J / cm 3 , the resist...

AI Technical Summary

Problems solved by technology

[0002] The earlier ceramic linear resistors were made of alumina and clay as the base material doped with carbon powder, because of their low sintering density and energy tolerance of less than 300 joules / cm 3 , and the resistance value drifts nearly 10% at 20-250°C, so it cannot meet the requirements for the use of high-energy absorbing resistor devices in power transmission and distribution systems; Chinese patent No. 96123503.9 discloses a zinc oxide ceramic linear resistor and its manufacturing method. The new ceramic resistors prepared by this method have the advantages of good temperature characteristics and high surge resistance, but the method described is a laboratory research technology and is not suitable for modern industrial production. The energy tolerance of its products is 680 joules / centimeter 3 , not exceeding 800 J / cm 3 , the resistivity is 1 ohm cm, the resistance range is narrow, and the voltage nonlinearity index is 1.26, which is obviously high, so its application field is greatly limited