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.APACHE is an air-hardening, cold-work die steel that exhibits less distortion during heat treatment than water or oil-hardening steel and many other air-hardening steels. Its low-distortion characteristic makes it attractive for applications where close size tolerance is important.