High temperature thermistor and manufacturing method thereof

Abstract

The invention relates to a high temperature thermistor and a manufacturing method thereof. The high temperature thermistor is formed by barium titanate, lead titanate, calcium titanate, strontium titanate, semi-conducting elements, silicon oxide, titanium oxide, alumina, manganese dioxide and magnesium oxide, wherein the semi-conducting elements are one or more of niobium oxide, yttrium oxide andantimony oxide. The manufacturing method is characterized by adding water to barium titanate, lead titanate and the like in a ball mill and finely grinding the mixture, discharging and drying the ground mixture, presintering the ground mixture for 2h, grinding the ground mixture in the ball mill, adding PVA adhesive solution, pelleting the mixture, forming the mixture through pressing by a tabletpress, sintering the formed material to obtain semi-conducting ceramics, carrying out grinding and spraying the Al electrode, thus obtaining the product. The sintering potential barrier is increased in the sintering process by adding the Mg element, thus ensuring the grains to be fine and uniform and the voltage resistance to be high. The ceramic structure is denser by replacing Ba with Mg, thus being capable of blocking ionic migration in the abominable atmosphere and improving the stability in the strongly abominable atmosphere. The high temperature thermistor can withstand 500V voltage under extremely low oxygen partial pressure by being assembled in a sealed Al pipe.

Description

technical field

[0001] The invention relates to a high-temperature thermistor and a manufacturing method thereof. Background technique

[0002] Due to the trend of global climate change, the issue of climate protection has been raised. Compared with the resistance wire heating element, the positive temperature coefficient thermistor is safe, reliable, and energy-saving, so it has been used in the heater heating device at present.

[0003] At present, the positive temperature coefficient thermistor used in the heater has (Pb, Ba)TiO3 as the main crystal phase, and the barium is replaced by lead, and its switching temperature is 200-300°C. The manufacturing method of this positive temperature coefficient thermistor is to use ball mill or dispersion ball mill to mix, press filter, lightly burn ball mill, then add binder to granulate, and then sinter in air at 1200-1400°C to form After ceramics, the electrodes are coated to form the thermistor chip. Its grain size is not easy...

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