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.ACI Type HH is an iron-chromium-nickel casting alloy having high heat, oxidation and corrosion resistance. It is recommended for furnace parts, salt pots, grate bars, belt conveyors and other parts operating up to 21008 F in intermittent service. It may be supplied in partially ferritic Type I or in wholly austenitic Type II depending on the applications and service requirements.