We can look at their chemical composition to find the difference between them. In fact, their main elements are not much different, only Mo and Cr are slightly different.
| Hastelloy C22 | Hastelloy C276 | |
| Chromium (Cr) | 22.0 - 24.0 | 14.5 - 16.5 |
| Nickel (Ni) | Balance | Balance |
| Molybdenum (Mo) | 12.5 - 14.5 | 15.0 - 17.0 |
| Tungsten (W) | 2.5 - 3.5 | 3.0 - 4.5 |
| Iron (Fe) | ≤ 2.0 | ≤ 4.0 - 7.0 (depending on grade) |
| Cobalt (Co) | ≤ 2.5 | ≤ 2.5 |
| Vanadium (V) | ≤ 0.35 | - |
| Silicon (Si) | ≤ 0.08 | ≤ 0.08 |
| Manganese (Mn) | ≤ 0.50 | ≤ 1.0 |
| Carbon (C) | ≤ 0.015 | ≤ 0.01 |
| Phosphorus (P) | ≤ 0.02 | ≤ 0.04 |
| Sulfur (S) | ≤ 0.02 | ≤ 0.03 |
In addition to looking at the chemical composition, the differences can also be found in their physical properties. For example: their density is different, Hastelloy C276 has a slightly higher density, Hastelloy C276 has a density of 8.9, and Hastelloy C22 has a density of 8.7.
Hastelloy C276 is based on the early C series with reduced C and Si content. It is designed to solve the problem that the Hastelloy C series has no resistance to intergranular corrosion in the welding state, but the alloy has poor thermal stability.
Hastelloy C22 is based on Hastelloy C276, which increases the alloy chromium content and reduces molybdenum and tungsten, so as to improve the use of C4 and C274 alloys in strong oxidizing medium corrosion. Although the corrosion resistance of oxidizing media has been improved, the pitting and crevice corrosion resistance has not been significantly improved.
In general, the corrosion resistance of Hastelloy C22 is better than that of Hastelloy C276 and C4 alloy. Hastelloy C22 is more resistant to local corrosion and high-temperature oxidation than Hastelloy C276, and can be understood as an upgraded version of Hastelloy C276.
GNEE is a supplier focusing on special steels. Choose GNEE for complex working conditions. Large-scale Hastelloy C276 and Hastelloy C22 are in stock with complete supply forms. Welcome to inquire online and send samples for free!
