Tool steel balls (fast steels and impact steels) are designed for extreme conditions of use: very high hardness, resistance to hot wear, toughness to shocks. The M2 and M50 grades (molybdenum fast steels) maintain their hardness up to 500–550 °C, making them essential in high temperature bearings and aerospace applications.
Materials available in tool steel
| Material | Standard USA | Hardness | Diameters |
|---|---|---|---|
| Steel plate for AISI D2 utensils | D2/T30402 | 55-65 HRC | 1 – 150 mm |
| Steel plate for AISI M2 utensils | M2/T11302 | 62-66 HRC | 1 – 150 mm |
| Steel plate for AISI M50 utensils | M50/T11350 | 60-65 HRC | 1 – 150 mm |
| S-2 steel tool steel shock resisting (rockbit) | T41902 | 54-63 HRC | 4.5 – 75 mm |
| Steel plate for AISI T15 utensils | T15 | 63-68 HRC | 1 – 150 mm |
Applications of tool steel beads
High temperature bearings (motors, turbines), drilling rods (Rockbit), impact and punch tools, aerospace applications and defence.
