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.CRUCIBLE 303 PLUS is an austenitic chromium-nickel stainless steel to which elements have been added to improve the machinability and non-galling characteristics.