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.Swissmetal alloy SM158N (Boillat 61B) is a free-machining brass with both machinability and cold workability. The alloy has been called heavy-leaded brass, clock brass, and engraver¿s brass.