ALUMINUM WIRE

General Description

Enamelled aluminum magnet wire is mainly used as an electrical conductor wherever coils are in motion. Because of the low density of aluminum, the coil weight can be reduced to one third of a similar copper coil. This weight advantage allows for easier and more efficient acceleration of the moving part, resulting in performance increases such as:  reduced access times of hard disk drives and improved sound quality & sensitivity for speakers and voice coils. For these applications, self-bonding aluminum wire is mainly used.
Enamelled aluminum magnet wires are available in diameters from 0.030mm to 0.500mm (AWG 48 - 24) with all insulation and self-bonding enamel types. All aluminum wire conforms to EN AW-1350A (E-Al) for use in the electrical industry and are guaranteed to meet conductivity requirements.
Besides enamelled aluminum wire, Elektrisola produces bare aluminum wire from 0.030mm to 0.500mm (AWG 48 - 24)

Features

  • Low density allows coil weight reduction
  • Rapid heat dissipation

Applications

  • VCM coils for HDD actuator
  • Voice coils (e.g. in Headphones)
  • High-Fidelity speakers
  • Induction heaters
  • Others

Typical values

CuAlCCA10%CCA15%HTCCA
% of copper by volume[%]1000101515
Density[kg/dm³]8.92.73.33.633.63
Resistance (IACS)[%]10062656762
Conductivity[S*m/mm²]58.535.8537.7039.1536
Resistivity[Ohm*mm²/m]0.01710.02790.02670.02560.0278
Solderability[-]goodno conventional solderinggoodgoodgood
Tensile strength[N/mm²]220-270120-140120-190150-230180-260

Soldering of Aluminum Wire

Soldering of aluminum is possible, but there are a number of critical areas that need tight control. Tenacious aluminum oxide makes most attempts to solder using conventional methods difficult. Flux must be used because of the rapid formation of an aluminum oxide layer, which is difficult to remove and prevents the solder from wetting the aluminum. The reason aluminum oxide is more difficult to remove compared to copper is because of its very high melting point of 2030°C, compared to the 660°C of pure aluminum. Another reason the aluminum oxide is difficult to remove is its high corrosion resistance value.  Therefore, more aggressive fluxes are often required, such as an organic amine-based flux (up to 285°C), or inorganic fluxes (e.g. sodium hydroxide up to 400°C). An ultrasonic soldering bath may also be used to crack the oxide layer and wet the aluminum without the use of flux.