View Sample Alloy Digest Data Sheet (PDF)Since 1952, Alloy Digest has been the leading reference for materials property data on metals and alloys used throughout the world. Featuring graphs, charts and tables, these sheets give facts and figures on composition or characterization, physical and mechanical properties, heat treatment, and machinability.COPPER ALLOY No. 220, previously called Commercial Bronze, 90%, is a copper-zinc alloy having good formability and resistance to stress-corrosion cracking.