Inconel 718 is a nickel-based superalloy known for excellent strength, corrosion resistance, and high-temperature performance. Its composition includes a balanced mix of nickel, chromium, iron, niobium, molybdenum, and other elements.
🔬 Typical Chemical Composition of Inconel 718 (% by weight)
| Element | Content (%) | Function |
|---|---|---|
| Nickel (Ni) | 50.0 – 55.0 | Base metal; provides corrosion & heat resistance |
| Chromium (Cr) | 17.0 – 21.0 | Enhances oxidation & corrosion resistance |
| Iron (Fe) | Balance | Matrix component |
| Niobium + Tantalum (Nb + Ta) | 4.75 – 5.50 | Precipitation hardening (γ" phase) |
| Molybdenum (Mo) | 2.80 – 3.30 | Strengthens alloy; improves creep resistance |
| Titanium (Ti) | 0.65 – 1.15 | Strengthening via precipitation (γ' phase) |
| Aluminum (Al) | 0.20 – 0.80 | Enhances γ' phase; adds oxidation resistance |
| Cobalt (Co) | ≤ 1.0 | Optional strengthening element |
| Carbon (C) | ≤ 0.08 | Controlled for toughness |
| Manganese (Mn) | ≤ 0.35 | Deoxidizer |
| Silicon (Si) | ≤ 0.35 | Deoxidizer |
| Sulfur (S) | ≤ 0.015 | Impurity; must be minimized |
| Phosphorus (P) | ≤ 0.015 | Impurity; must be minimized |
| Copper (Cu) | ≤ 0.30 | Residual element |
| Boron (B) | ≤ 0.006 | Grain boundary strengthening (very small amount) |
