Alloy: 642 | Material: Bronze | Shape: Bar/Round | Diameter 0.625 Inches | Item Length: 12 Inches Bronze Round Bar 642 is an aluminum-silicon bronze that offers high strength, excellent corrosion resistance, good fatigue resistance, anti-galling properties, and high machinability. 642 has the highest machinability rating of any non-leaded bronze, additionally the high aluminum and silicon contents make this one of the lightest bronzes. Brazing and most forms of welding are only rated as fair though. This material is typically used to make blots, gears, and valves. Bronze is an alloy of copper which can vary widely in its composition. It is often used where a material harder than copper is required, where strength and corrosion resistance is required and for ornamental purposes. The variations in bronze (both in proportion and elemental composition) can significantly affect its weathering characteristics. "True" bronze is a combination of approximately 90% copper (Cu) and 10% tin (Sn), however there are three major classes or types of "bronzes" used in sculpture and construction. UNS C64200, CDA 642, C642 This product weighs 1.03 pounds and meets the following specs: ASTM-B150, AMS-4634