Alloy 825 (Incoloy 825, UNS N08825) is a nickel–iron–chromium alloy with additions of molybdenum, copper, and titanium. Its tightly controlled chemical composition provides excellent resistance to corrosion in harsh environments including chemicals, acids, seawater, and oil & gas applications.
| Element | Composition Range |
|---|---|
| Nickel (Ni) | 38.0 – 46.0% |
| Iron (Fe) | Balance (typically 22 – 30%) |
| Chromium (Cr) | 19.5 – 23.5% |
| Molybdenum (Mo) | 2.5 – 3.5% |
| Copper (Cu) | 1.5 – 3.0% |
| Titanium (Ti) | 0.6 – 1.2% |
| Manganese (Mn) | Up to 1.0% |
| Silicon (Si) | Up to 0.5% |
| Carbon (C) | Maximum 0.05% |
| Sulfur (S) | Maximum 0.03% |
| Aluminum (Al) | Up to 0.2% |
For design or procurement purposes, always verify the exact composition against relevant standards (ASTM B423, ASTM B424, ASTM B425, UNS N08825) or the mill certificate from the supplier to ensure values fall within specified ranges.