Age-Hardenable Electrical Contact-Spring Material

There is at present no satisfactory material available that can comply with all three of the most important criteria of a make-break spring contact, i.e. good spring properties, switching capability, and contact-resistance stability. As the result of a development program, a monolithic contact-spring material, composed of an age-hardening silver-palladium-copper alloy that satisfied these criteria was devised. The background theory and the melting, fabrication, and testing of the alloy are described. Its performance in actual relay applications and anticipated improvements are also given.