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.UGIMA 4021 and UGIMA 420A are identical grades that are differently named for the European and North American markets, respectively. The grade is similar to UNS S42000 and is a hardenable martensitic stainless steel with a higher carbon content than type 410. UGIMA 4021/420A contain an addition of calcium by the UGIMA process. This steelmaking technique produces malleable oxide inclusions with a low melting point. The inclusions then lubricate the metal-tool interface in machining and improve productivity.