Spiral Elongation Test

A method of assessing the suitability of copper wire for enameling. Ductility properties are deter­mined by annealing the wire at 200°C (392°F), winding it into a coil and elongating it by a given load. The weight is released and the length of the stretched coil measured. Longer is better as a larger elongation means less elastic recovery and more ductility.