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.ALUMINUM A108 is a non-heat treatable permanent mold aluminum casting alloy havinng good casting characteristics and pressure tightness. It is recommended for general purpose castings.