Electroforge consists on enlarging the transversal section of a bar, wheter at an end or a central zone, by means of combining a permanent axial force with electrical heating of the material, which is being displaced between a fixed muffle and a shiftable anvil. This procedure is mandatory when forge lenght is over 3 times bar diameter. Axial force is attained by means of a piston that pushes the material against another piston that shifts slowly enough to make room for forged material. This is the method used for forging poligonal and circular section bars, made of steel, bronze, aluminium alloys, etc.
The "veins" or forgin lines on the material are continuous, no folds, no sharp curves, following the general shape of the forged section. This yields higher mechanic resistence pieces, more durable, with an optimal microstructure.