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.EXTENDO-DIE hot work die steel is covered by US Patent No. 4,853,181. The steel combines extreme toughness with good red hardness in large section sizes. Although primarily used as a hot work tool steel, Extendo-Die may be considered for many cold work applications, particularly in large sections, where AISI H13 tool steel is currently used.