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.HS-105 is often called 5% Co HSS (high-speed steel). It has some of the increased red-hardness properties of M42 and is not quite as susceptible to shock. It is often used for making tool bits.