Alloy 625 (UNS N06625) is a nonmagnetic nickel-chromium-molybdenum alloy that is used in a wide range of severely corrosive environments due to its high strength, its high toughness and its excellent corrosion resistance. The strength of alloy 625 is mainly derived from the stiffening effect of molybdenum and niobium on its nickel-chromium matrix. The alloy 625 also has excellent fatigue strength and stress corrosion cracking resistance to chloride ions. Weldability of Alloy 625 material is very also good.
Some of the applications for Alloy 625 are gate and wing valves, subsea chokes, ring gaskets and components for gas turbines and chemical plants.
The data above based on ASTM B446 Grade 1, AMS5666 and NACE MR0175/ ISO15156-3:2015
| Carbon(C) | Manganese(Mn) | Phosphorus(P) | Sulfur(S) | Silicon(Si) | Nickel(Ni) | Cobalt(Co) |
| 0.10 Max | 0.50 Max | 0.015 Max | 0.015 Max | 0.50 Max | Min 58.0% | 1.00 Max |
| Chromium(Cr) | Molybdenum(Mo) | Niobium + Tantalum(Nb (Cb) + Ta) | Titanium(Ti) | Copper(Cu) | Aluminum(Al) | Iron (Fe) & Others |
| 20.00%-23.00% | 8.0%-10.0% | 3.15%-4.15% | 0.40% Max | — | 0.4% Max | RemainderFe 5.0 Max |