NTC Thermistor - Electrode Body Choice
Thermistor is a kind of sensitive element, the basic sensing element structure is that the sensitive substrate material, electronic ceramics, and electrode wire (some do not need outer lead, such as electronic component), sealing cover.It is the biggest characteristic is changing the resistance with temperature, therefore can through its resistance value perception of ambient temperature changes.
Obviously, if only the electronic ceramic substrate cannot be changed the temperature change which caused by the quantity of electricity, when converted to facilitate testing of the substrate will not be able to use.
Thermistor is used in electronic components in sensor circuit, only as the substrate and electrode can be normally used in the circuit.Visibly, thermistor electrode plays a very important role.
The present status of NTC thermistor electrode in the manufacturing are metal material, such as Ag, Ag - Pa, Au, Pt, etc (working temperature is high, such as 1000 degrees may consider using platinum paste).In the production of the NTC thermistor electrode, domestic manufacturers generally used silver paste for electrodes, sometimes use the Ag - Pa pulp, and the gold slurry were useds electrode materials in some foreign products.
The electrode materials existing problems:
Silver paste are generally used electrode materials as the domestic manufacturers of NTC thermistor production.
Its biggest flaw is silver ion migration in the substrate material easily affect the performance of the matrix element, and not all materials are suitable for silver paste for electrode. Some material with silver paste also can produce the adhesion strength is not good, easy to fall off. Recent data show that in the aspect of PTC thermistor and piezoelectric ceramic electrode making have been using aluminum and nickel starched, and NTC thermistor electrode is still silver paste. Most of the foreign brands use gold pulp.