Discaloy 16 is a historical iron-nickel-chromium superalloy, cross-referenced to SAE/AMS 5725. The original Discaloy alloy (roughly Fe-26Ni-13.5Cr-2.75Mo-1.75Ti) leans on titanium-driven gamma-prime precipitation for its strength - the same hardening mechanism later refined into A-286 - and is generally regarded as a direct iron-base precursor to that alloy. The "16" variant covered here carries noticeably higher chromium (~16%) and molybdenum (~6%) than the original grade, placing it closer to the related 16-25-6 family also documented under AMS 5725, where Cr and Mo contribute more solid-solution strengthening to the austenitic matrix alongside the titanium precipitation effect.

Alloys in this family were developed in the 1940s-50s as an economical, easier-to-produce iron-base alternative to full nickel-base superalloys, aimed at jet-engine turbine discs, rotors, shafts, and high-temperature fasteners that needed to hold strength at elevated temperature without the cost of a heavier nickel-base grade. Discaloy-type material remains a useful reference point for anyone machining early-generation aerospace hardware or restoring legacy turbine components built to these historical specifications.

Only the SAE/AMS 5725 cross-reference and the composition shown below could be confirmed against current published reference data. Additional international designation equivalents sometimes listed for this alloy on older charts could not be verified and are intentionally omitted rather than guessed.

As an iron-base heat-resistant superalloy, Discaloy 16 machines more readily than a true nickel-base superalloy, but it still cuts noticeably harder than a standard stainless or low-alloy steel. Its combined 16% chromium and 6% molybdenum content raise flank wear compared with lower-alloy iron-base grades like A-286, and the alloy's reduced thermal conductivity concentrates heat at the tool-chip interface faster than it would in a plain alloy steel.

The material work-hardens readily under light or interrupted cuts, so a steady, adequate chip load matters - rubbing or hesitating at the cutting edge raises a hardened skin that is tougher to remove on the next pass. Because it retains a meaningful share of its strength at elevated temperature, tool edges stay under real mechanical load even as cutting temperatures climb, which is why sharp, positive-rake geometries, rigid workholding, and generous coolant delivery matter more here than on a comparable carbon or low-alloy steel. Coated carbide grades developed for superalloys and high-temperature stainless steels are the standard choice for this alloy family.