Bearing steel

Description of rolling bearing steel tubes Ovako 803 (100Cr6)

Characterised by high resistance to fatigue and wear. The tubes are supplied in annealed condition and are easy to machine. Up to 60-65HRC can be achieved by martensitic hardening/tempering.

Properties

Usually supplied as soft-annealed tubes. The following mechanical properties can be achieved:

Forging: 800-1100°C, cooling in still air.

Soft annealing: Heat up to 820°C /1 hour, hold at 820°C for 2 hours, cool down from 820°C to 740°C / 1 hour, cool down from 740°C to 690°C /10 hours, cool down in still air.

Stress-relief annealing: 550-650°C, holding time 1 hour, cooling in air.

Martensitic hardening: 830-870°C / 10-60 minutes, quenching in oil and tempering within 2 hours to min. 160°C according to data sheet.

Bainitic hardening: 850-875°C / 10-60 minutes, quenching in salt bath 220-250°C /3-7 hours according to data sheet.

Tempering: 160-570°C according to data sheet, cooling in still air.

Rolling bearing steel tubes and Ovako® 824 (100CrMo7)

Suitable for through-hardening thicker wall thicknesses. This steel also has high fatigue strength, excellent wear resistance and good toughness. This grade is suitable for martensitic and bainitic hardening.

Properties

Usually supplied as soft-annealed tubes. The following mechanical properties can be achieved:

Forging:                             800-1100°C, cooling in still air

Soft annealing:                 Heat up to 820°C /1 hour, hold 820°C 2 hours, cool down from 820°C to 740°C / 1 hour, cool down from 740°C to 690°C /12 hours, cool down in still air.

Stress-relief annealing:  550-650°C, holding time 1 hour, cooling in still air.

Martensitic hardening:   830-870°C / 10-60 minutes, quenching in oil and tempering within 2hours.
 
Bainitic hardening:         850-875°C / 10-60 minutes, quenching in salt bath 220-250°C/3-8 hours

Tempering:                     160-500°, cooling in still air.