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 6151, formerly A51S Alloy, is an aluminum forging alloy combining good forgeability, strength, and resistance to corrosion. It responds to an age-hardening heat treatment.