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.KOVAR A is a cobalt, nickel, iron alloy recommended for sealing into hard glass. Has similar expansion curve as glass, makes firm bond between metal and glass, is easy to machine and form, and has high resistance to thermal shock.