ABSTRACT
The crystal lattices of cold worked metals are deformed and may be highly imperfect, depending upon the amount of deformation. Metals and alloys also show changes in electrical resistivity as they are strained within their "elastic" limits. Large numbers of alloys intended for electrical applications are commercially available. The temperature coefficients of resistivities of alloys must be known if resistance materials are to be used properly in engineering applications. The temperature coefficient of resistivity, is very sensitive to the small quantities of impurity elements present in solution in a "pure" metal. Many engineering alloys which derive desirable sets of mechanical properties from precipitation phenomena must be used with caution, if at all, in electrical applications. The reason for this is that small changes in the precipitates, which may occur over long times, may cause relatively large changes in the electrical properties, even at room temperature.
