Alloy 690 is a high-chromium nickel alloy having excellent resistance to many corrosive aqueous media and high temperature atmospheres. The alloy’s high chromium content gives it excellent resistance to caturisation, metal dusting, oxidation and sulfidation at high temperature. In addition to its corrosion resistance, alloy 690 has high strength, good metallurgical stability, and favorable fabrication characteristics.
Available tube product forms
Typical Applications
- Heat exchangers
- Steam Generators
- High temperature applications exposed to caustic solutions
Typical manufacturing specifications
- ASTM B167
- Also individual customer specifications.
Industries predominantly using this grade
Technical Data
Mechanical Properties
| Temper |
Annealed |
| Tensile Rm |
86 |
ksi (min) |
| Tensile Rm |
590 |
MPa (min) |
| R.p. 0.2% Yield |
35 |
ksi (min) |
| R.p. 0.2% Yield |
240 |
MPa (min) |
| Elongation (2” or 4D gl) |
≥30 |
% (min) |
Physical Properties (Room Temperature)
| Specific Heat (0-100°C) |
450 |
J.kg-1.°K-1 |
| Thermal Conductivity |
13.5 |
W.m -1.°K-1 |
| Thermal Expansion |
14 |
μm/μm/°C |
| Modulus Elasticity |
211 |
GPa |
| Electrical Resistivity |
1.26 |
μohm/cm |
| Density |
8.2 |
g/cm3 |
Chemical Composition (% by weight)
| Element |
Min |
Max |
| C |
- |
0.05 |
| Si |
- |
0.5 |
| Mn |
- |
0.5 |
| P |
- |
0.02 |
| S |
- |
0.015 |
| Al |
- |
0.5 |
| Cr |
27 |
31 |
| Cu |
- |
0.5 |
| Fe |
7 |
11 |
| Ti |
- |
0.5 |
| Ni |
Balance |