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.SOLAR TOOL STEEL is a very tough water hardening tool steel. Even at Rockwell C 59/60, it will bend before breaking. If medium and large sections, the steel develops a hard case and tough core when hardened.