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.LESCALLOY 4340 VAC-ARC is a low-alloy steel that can be heat treated to high strength levels. It has a good combination of strength, ductility and toughness along with high hardenability. It is produced by the vacuum-consumable-electrode process to provide optimum cleanliness and preferred ingot structure. It is used for aircraft components including retainer rings for critical bearings and other heavy-duty applications.