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.CARPENTER NO. 158 ALLOY is a chromium-nickel carburizing steel ideally suited for jobs requiring an extra measure of core strength in sections up to 5 inches thick. Additionally, the steel develops high wear resistant case characteristics when carburized and hardened.