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.AISI 4145 is a through-hardening, medium-carbon chromium-molybdenum steel recommended for heavy-duty service. It is suitable for a wide variety of engineering uses.