Specilized Size Constantan/ 6J40 Precision Resistance Alloy Foil/ Strip/ Sheet

Constantan is one of the most widely used alloys. This is owing to the fact that it has the best overall composition of the important properties that is needed for many of the strange gauge applications. Constantan has the highest resistivity among all the other alloys, which makes it insensitive to the level of strain and temperature. Its resistivity is so high that it can also achieve suitable resistance levels in very small grids also. The temperature coefficient of resistance is not at all excessive in case of constantan alloy. Therefore it has very many advantages over the other alloys.

Constantan has a good fatigue life and a very high elongation capacity also. All these additional properties make it a highly useful and good alloy. But this alloy shows drift at the temperature range of 65 °C, therefore this point should be kept n mind when one tests the stability strain if the gauge, since its stability strain is critical at this temperature.

Constantan Applications

The application of constantan falls in three important categories:

Temperature Measurement

Constantan is used for the formation of thermocouples with the wires of copper, iron and chromel. It is used to form Chrome- constantan thermocouples and good iron constantan thermocouples also.

Heavy Duty Industrial Rheostats

Constantan is an ideal alloy for the electric motor starter resistances and for heavy duty industrial rheostats. Since it has a high specific heat resistance, and a good ductile nature, it satisfies the entire important requirement for this category of specifications. Constantan is transformed into wires of large size or this kind of requirements.

Wire Wound Precision Resistors

Constantan is one of the most widely used alloys in wire wound precision resistors, volume control devices and temperature stable potentiometers. It is a main attraction in this field owing to the fact that it has negligible temperature coefficient and high resistance.

Development of a high thermal E.M.F – This is another important property of constantan, that it develops a high thermal E.M.F against other metals. It is therefore used in thermocouple alloys, with other metals like iron and copper.