Copper-clad steel

American engineers in 1883 and again in the 1890s made attempts to produce a copper-steel wire, in one instance at least, by electroplating copper on steel.

Copper-clad steel is occasionally used for making durable radio antennas, where its HF conductivity is nearly identical to a same-diameter solid copper conductor.

The main properties of these conductors include: Since the outer conductor layer is low-impedance copper, and only the center is higher impedance steel, the skin effect gives RF transmission lines with heavy copper-cladding a low impedance at high frequencies, equivalent to that of a solid copper wire.

Due to the inseparable union of the two metals and the low amount of the more costly one, it deters theft since copper recovery is impractical and thus has very little scrap value.

Installations with copper-clad steel conductors are generally accepted as fulfilling the legal specifications for a good electrical ground.