general characteristics

Alumel is a nickel-based alloy (93−96%); Which is alloyed: Al (≤2,4%); Si (≤1.2%); Mn (≤2.2%). With a resistivity of 0.32 Ohmmmm ² / m, the coefficient of linear thermal expansion is 13.6 x 10 ^-6 / C °, the density reaches 8.5 g / cm ³, melting point 1430 ° C. From this alloy produce wire, circle, tape for thermocouples.

High nickel content increases the cost of wire. The ability of nickel to dissolve other metals without loss of plasticity allows you to change the composition of the alloy. For example, cobalt increases thermal emf, heat resistance, corrosion resistance, ductility. Nickel loses its plasticity when it interacts with sulfur, because of the formation of sulphide, fragility increases. To eliminate this disadvantage, silicon is introduced into the alloy and the percentage of aluminum is reduced. This allows a longer service life at t ° above 900 ° C.

Application in pyrometry

Alumel is used in the form of a negative thermoelectrode alumel-chromel. Due to its high plasticity, it is used in the form of tapes, wires, compensating wires. And to improve the performance of the alloy, zirconium is added to it up to 0.1% or 0.06% Zr together with 0.005% B. Doping can increase strength, ductility at t ° up to 1000 ° C, and also increase the stability of thermo-emf at T ° to 1320 ° C. Doping allows the use of alumel for measurements at temperatures up to 1320 ° C, and used in an aggressive environment.

Thermocouples and temperature controllers

The most common wire is alumel for making thermocouples. When heated, a potential difference arises between the heterogeneous conductors, which grows with increasing temperature. If you set the error factor depending on the type of thermocouple, you can get the measured temperature data to within a degree. Thermocouple has found wide application in metallurgical equipment as a temperature sensor for thermal furnaces, as well as in all kinds of industrial heating installations and temperature controllers.

Compensating wires and sensors

Alumel wires produce compensating wires widely used in the automotive, aerospace, and scientific and technical research. Alumel-Chromel sensors are connected to measuring devices, connect the thermocouple with the converter. The use of Alumel-Chromel pair provides a high measurement accuracy, and also facilitates the weight of the sensors.

Buy at the best price

To get acquainted with more in detail with products, to clarify its basic qualities, to place an order most simply through our website www.vmc.com.ua/. The company offers a huge range of Alumel wire, the high quality of products and the absence of intermediaries determine the most profitable offers for solving current production problems. Delivery in the shortest time in any region of the country and abroad, compliance with regulatory products has long won the trust of permanent Due to its high performance, Alumel has been very popular in many areas of production.