Alloy 625 is a nickel-chromium alloy used for its high strength, excellent fabricability and outstanding corrosion resistance. Service temperatures can range from cryogenic to 980°C (1800°F). Alloy 625 strength is derived from the solid solution strengthening effect of molybdenium and niobium on its nickel-chromium matrix.
Thus precipitation-hardening treatments are not required. This combination of elements also is responsible for superior resistance to a wide range of corrosive environments of unusual severity as well as to high-temperature effects such as oxidation and carburization.
Available tube product forms
Typical Applications
Typical manufacturing specifications
- ASTM B444
- AMS 5581
- BS 3074
- Also individual customer specifications.
Industries predominantly using this grade
Technical Data
Mechanical Properties
| Temper |
Annealed (Grade1) |
Solution-treated (Grade 2) |
| Tensile Rm |
120 |
ksi (min) |
100 |
ksi (min) |
| Tensile Rm |
827 |
MPa (min) |
690 |
MPa (min) |
| R.p. 0.2% Yield |
60 |
ksi (min) |
40 |
ksi (min) |
| R.p. 0.2% Yield |
414 |
MPa (min) |
276 |
MPa (min) |
| Elongation (2” or 4D gl) |
30 |
% (min) |
30 |
% (min) |
Physical Properties (Room Temperature)
| Specific Heat (0-100°C) |
460 |
J.kg-1.°K-1 |
| Thermal Conductivity |
14.8 |
W.m -1.°K-1 |
| Thermal Expansion |
12.4 |
μm/μm/°C |
| Modulus Elasticity |
207 |
GPa |
| Electrical Resistivity |
10.3 |
μohm/cm |
| Density |
8.42 |
g/cm3 |
Chemical Composition (% by weight)
| Element |
Min |
Max |
| C |
- |
0.1 |
| Si |
- |
0.5 |
| Mn |
- |
0.5 |
| P |
- |
0.015 |
| S |
- |
0.015 |
| Al |
- |
0.4 |
| Cr |
20 |
23 |
| Cu |
1 |
1.4 |
| Fe |
- |
5 |
| Mo |
8 |
10 |
| Nb |
3.15 |
4.15 |
| Ni |
Balance |
| Ti |
- |
0.4 |