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.HALCOMB 218 is a tough hot work steel suitable for tools requiring a higher degree of toughness at moderately elevated temperatures than is obtainable in the tungsten types of hot work steel. It is similar to ASM Type IV-B and AISI H-11.