M4 Tool Steel Technical Data
M4 is another in the Molybdenum High Speed Tool Steels. It has a relatively high 1.3% carbon content for high hardness and excellent wear resistance.
| Carbon | 1.25 - 1.4 |
| Chromium | 3.75 - 4.75 |
| Iron | Balance |
| Manganese | 0.15 - 0.4 |
| Molybdenum | 4.25 - 5.5 |
| Phosphorus | 0.03 max |
| Silicon | 0.2 - 0.45 |
| Sulphur | 0.03 max |
| Tungsten | 5.25 - 6.5 |
| Vanadium | 3.75 - 4.5 |
| Specific Gravity | 0.288 lb/in3 |
| Strength | 60,000 psi |
| Hardness, Rockwell C | 65 |
| Modulus of Elasticity | 30000 ksi |
| Izod Impact Unnotched | 33 ft-lb |
| Machinability | 35 - 40 % |
| CTE, linear 20°C | 6.23 μin/in-°F |
| CTE, linear 500°C | 6.81 μin/in-°F |