Abstract: A gold based electrical contact material comprising an oxide of an oxidize element in the gold matrix formed by subjecting the solid solution to an oxidizing atmosphere for internally oxidizing the oxidizable element is presented. Such internal oxidation forms hard second phase oxide particles dispersed throughout the solution having high wear resistance, high hardness, high strength and high conductivity with homogeneous and uncontaminated structure.

Abstract: An electrical commutator having a plurality of spaced apart commutator bars is disclosed. The commutator bars are formed from a composite of an electrically conductive copper portion bonded, for example by brazing or electron beam welding, at an interface to a steel body which is geometrically designed to reduce the bending and longitudinal stiffness of the body, whereby the shear stress at the interface is reduced during operation.

Abstract: An aluminum electrical conductor is electrically joined to a copper electrical conductor by a cold weld lap joint which is substantially free of copper-aluminum intermetallic compounds. The overlapped portions of the conductors are deformed at least 74% and no greater than 82% to achieve a weld joint which has both excellent physical properties and excellent electrical properties. The cold weld lap joint is a reliable electrical connection for electrical circuits experiencing current densities of more than 1000 amperes per square inch and a sustained high temperature of 125.degree. C. and above.