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.AIRQUE is an intermediate chromium-molybdenum air-hardening die steel which finds its best application in intricate dies where difficulty in distortion and cracking is encountered with the usual oil-hardening types of tool steels. It is classed as type A-2 tool steel.