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.THERMO-SPAN ALLOY is a precipitation-hardenable superalloy with a low coefficient of expansion combined with tensile and stress-rupture strength. Thermal fatigue resistance is inherent.