Product data for Sanbar® 20 hollow drill steel
Sanbar® 20 is a high strength chromium-molybdenum steel with high fatigue strength and excellent wear resistance in the as-rolled condition.
Applications
Sanbar® 20 is used for integral drill steels, pilot rods and tapered rods.
Mechanical properties
| Proof strength Rp0.2 MPa (ksi) |
Tensile strength Rm Mpa (ksi) |
Hardness |
|---|---|---|
| 850 (123) | 1300 (189) | 37-43 HRC |
Decarburization
The maximum permissible decarburization depth is 0.20 mm (0.008 in.) on the outer surface and 0.10 mm (0.004 in.) on the inner surface.
Machinability
Machining may require prior annealing.
Forging
Induction heating to 1000–1100°C (1830– 2010°F), 10–20 seconds. Cooling in air. Forging range 1100–850°C (2010–1560°F).
Read more about forging of Sanbar 20
Heat treatment
Annealing (induction heating) 850–900°C (1560–1650°F). Cooling in air.
Read more about heat treatment of Sanbar 20
Normalizing (induction heating)
950–1050°C (1740- 1920°F). Cooling in air. Hardening of shank end (through hardening). Read more about shank end hardening of Sanbar 20
Hardening
Induction heating to 1000–1100°C (1830- 2010°F). Forced cooling in air or oil.
Tempering
Recommended hardness 50 HRC, temperature appr. 500°C (930°F)/0.5 hours. Tempering within one hour after hardening.