While not the most resistant alloy for nitriding environments at traditional 1000°F to 1200°F (540°C to 650°C) temperatures, 214 alloy exhibits outstanding resistance at the higher temperatures where its protective Al2O3 scale can form, even in extremely low oxygen environments. Tests were performed in flowing ammonia at 1200, 1800 and 2000°F (650, 980 and 1095°C) for 168 hours. Nitrogen absorption was determined by technical analysis of samples before and after exposure, and knowledge of the exposed specimen area.
| Alloy |
Nitrogen Absorption (mg/cm2) |
| 1200°F (649°C) |
1800°F (982°C) |
2000°F (1093°C) |
| 230® |
0.7 |
1.4 |
1.5 |
| 600 |
0.8 |
0.9 |
0.3 |
| 625 |
0.8 |
2.5 |
3.3 |
| 601 |
1.1 |
1.2 |
2.6 |
| 214® |
1.5 |
0.3 |
0.2 |
| X |
1.7 |
3.2 |
3.8 |
| 800H |
4.3 |
4.0 |
5.5 |
| 310 SS |
7.4 |
7.7 |
9.5 |