Electromagnetic Actuators Suitable for High Temperatures Using Thin Aluminum Foil as Conductor

Electromagnets are widely used as drive elements in many technical areas, e.g. as control elements for valves. The technical requirements include, for example, static and dynamic electromagnetic properties, compact design and reliability. On the economic side, the total costs must be considered. Copper (Cu) is predominantly used as a conductor material for electromagnets. However, this is problematic due to the fluctuating market prices of the metal. For example, the raw material prices for Cu have doubled somewhat between 2016 and 2022. In this paper, as an alternative to coils made of round Cu wire, options are sought for producing coils from anodised aluminum (AI) foil. For this purpose, the advantages and disadvantages of round Cu wire and Al foil are discussed with regard to material properties, manufacturing processes and handling. First, technical concepts for the realisation of this replacement are reported. Then the cylindrical coil is manufactured from anodised Al coil and a prototype of a cylindrical coil is built for demonstration. The newly manufactured coils are tested against the conventional coils made of Cu and the results of the comparison are presented.