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.Rex 49 is a high-speed tool steel designed to give much longer life in machining difficult to cut metals such as highly-alloyed steels, stainless steels, superalloys, and titanium. Rex 49 heat treated to 67/69 Rockwell C makes it outstanding for difficult machining operations.