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.ALLEGHENY LUDLUM 204 & 204L are austenitic chromium-nickel-manganese stainless steels comparable in properties to Type 304 and 304L stainless steels.