The most widely used phosphor bronze contains 0.2% phosphorous and 5% tin; It has only half the conductivity of its most popular brass cousin, copper-30% zinc (15% IACS vs. 28% IACS). Unlike the brasses, which have a rather wide range of electrical conductivity (28-56% IACS), most phosphor bronzes range from only 11 up to 20% IACS , although there are exceptions with higher conductivity.
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