Improved Phosphor Bronzes and Improved Copper-Tin-Zinc Alloys in Very Light (Foil) Gauges for Z-Axis Type Applications

摘要

The trend of increasing densification in connector designs has resulted in the need for miniaturizing the connector spring contacts. This includes the use of Z-Axis type of connectors. As a result the connector spring materials will continue to thin down to gauges that may be significantly lighter than those currently used. These gauges will likely be less than .003° thick. The mechanical properties of these thinner gauges (tensile and yield strength, elongation and other formability factors) are not well understood. This may be partly due to factors which are metallurgical and geometry related, factors that deal with accurate and repeatable testing capability of available testing equipment and also some interpretational issues. This paper covers test results on light gauge strip, of the order of .002* thickness, in alloys in the improved phosphor bronze and improved copper-tin-zinc alloy families. The results show that the tensile and yield strengths of these very light gauges are very similar to those at conventional, higher thicknesses. The test data also shows equal or better formability. This paper provides important information for designers, who are considering component applications made with very light gauge foils/ strips.