Effect of Alloying Elements in Steel
| ALLOYING ELEMENT |
HARDNESS | STRENGTH | YIELD POINT / YIELD STRENGTH |
ELONGATION | REDUCTION OF AREA |
IMPACT RESISTANCE |
ELASTICITY | HIGH-TEMPERATURE RESISTANCE |
COOLING RATE | CARBIDE FORMATION |
WEAR RESISTANCE |
FORGEABILITY | MACHINABILITY | OXIDATION TENDENCY |
CORROSION RESISTANCE |
| Si | ↑ | ↑ | ↑↑ | ↓ | ῀ | ↓ | ↑↑↑ | ↑ | ↓ | ↓ | ↓↓↓ | ↓ | ↓ | ↓ | ῀ |
| Mn* | ↑ | ↑ | ↑ | ῀ | ῀ | ῀ | ↑ | ῀ | ↓ | ῀ | ↓↓ | ↑ | ↓ | ῀ | ῀ |
| Mn** | ↓↓↓ | ↑ | ↓ | ↓↓↓ | ῀ | - | - | - | ↓↓ | - | - | ↓↓↓ | ↓↓↓ | ↓↓ | ῀ |
| Cr | ↑↑ | ↑↑ | ↑↑ | ↓ | ↓ | ↓ | ↑ | ↑ | ↓↓↓ | ↑↑ | ↑ | ↓ | - | ↓↓↓ | ↓↓↓ |
| Ni* | ↑ | ↑ | ↑ | ῀ | ῀ | ῀ | - | ↑ | ↓↓ | - | ↓↓ | ↓ | ↓ | ↓ | ῀ |
| Ni** | ↓↓ | ↑ | ↓ | ↑↑↑ | ↑↑ | ↑↑↑ | - | ↑↑↑ | ↓↓ | - | - | ↓↓↓ | ↓↓↓ | ↓↓ | ↑↑ |
| Al | - | - | - | - | ↓ | ↓ | - | - | - | - | - | ↓↓ | - | ↓↓ | |
| W | ↑ | ↑ | ↑ | ↓ | ↓ | - | - | ↑↑↑ | ↓↓ | ↑↑ | ↑↑↑ | ↓↓ | ↓↓ | ↓↓ | - |
| V | ↑ | ↑ | ↑ | ῀ | ῀ | ↑ | ↑ | ↑↑ | ↓ | ↑↑↑↑ | ↑↑ | ↑ | - | ↓ | ↑ |
| Co | ↑ | ↑ | ↑ | ↓ | ↓ | ↓ | - | ↑↑ | ↑↑ | - | ↑↑↑ | ↓ | ῀ | ↓ | - |
| Mo | ↑ | ↑ | ↑ | ↓ | ↓ | ↑ | - | ↑↑ | ↓↓ | ↑↑↑ | ↑↑ | ↓ | ↓ | ↑↑ | - |
| S | - | - | - | ↓ | ↓ | ↓ | - | - | - | - | - | ↓↓↓ | ↑↑↑ | - | ↓ |
| P | ↑ | ↑ | ↑ | ↓ | ↓ | ↓↓↓ | - | - | - | - | - | ↓↓↓ | ↓↓↓ | ↓↓ | ↑↑ |
| * in pearlitic steels | |||||||||||||||
| ** in austenitic steels | |||||||||||||||
| ↑ increases | |||||||||||||||
| ↓ decreases | |||||||||||||||
| ῀ unchanged | |||||||||||||||
| - insignificant or unknown |
