Tin be toxic. Tin in combination with other elements forms a wide variety of useful alloys. Tin is most commonly alloyed with copper. Pewter is 85–99% tin; bearing metal has a high percentage of tin as well. Bronze is mostly copper (12% tin), while addition of phosphorus gives phosphor bronze. Bell metal is also a copper–tin alloy, containing 22% tin. Tin has sometimes been used in coinage; for example, it once formed a single-digit percentage (usually five percent or less) of American and Canadian pennies. Because copper is often the major metal in such coins, sometimes including zinc, these could be
Copper in heat exchangers titanium. This article focuses on beneficial properties and common applications of copper in heat exchangers. New copper heat exchanger technologies for specific applications are also introduced. Heat exchangers using copper and its alloys have evolved along with heat transfer technologies over the past several hundred years. Copper condenser tubes were first used in 1769 for steam engines. Initially, the tubes were made of unalloyed copper. By 1870, Muntz metal, a 60% Cu-40% Zn brass alloy, was used for condensers in seawater cooling. Admiralty metal, a 70% Cu-30% Zn yellow brass alloy with 1% tin added to improve corrosion resistance, was