Rolling element bearing having bainite microstructure

A rolling element bearing prepared according to a process comprising:

• forming an inner raceway and an outer raceway, wherein at least one of the inner raceway and the outer raceway is composed of a steel alloy consisting of:
• 0.7 to 0.9 wt. % carbon,
• 0.1 to 0.4 wt. % silicon,
• 0.7 to 0.9 wt. % manganese,
• 1.5 to 1.8 wt. % chromium,
• 0.2 to 0.4 wt. % molybdenum,
• 0 to 0.25 wt. % nickel,
• 0 to 0.3 wt. % copper,
• 0.05 to 0.2 wt. % vanadium,
• 0 to 0.2 wt. % cobalt,
• 0 to 0.2 wt. % aluminium,
• 0 to 0.1 wt. % niobium,
• 0 to 0.2 wt. % tantalum,
• 0 to 0.05 wt. % phosphorous,
• 0 to 0.03 wt. % sulphur,
• 0 to 0.075 wt. % tin,
• 0 to 0.075 wt. % antimony,
• 0 to 0.075 wt. % arsenic,
• 0 to 0.01 wt. % lead,
• 50 to 350 ppm nitrogen,
• up to 15 ppm oxygen,
• less than 10 ppm calcium,
• up to 50 ppm boron, and
• up to 50 ppm titanium, the balance being iron and unavoidable impurities,
• austenitizing the at least one of the inner raceway and the outer raceway composed of said steel alloy at 800° C.-890° C. for 10 to 120 minutes;
• through-hardening the austenitized inner raceway and/or outer raceway by quenching;
• heating the through-hardened inner raceway and/or outer raceway to form bainite until bainite transformation has ceased and the inner raceway and/or outer raceway has a uniform bainite microstructure;
• and
• assembling the rolling element bearing by disposing a plurality of rolling elements between the inner raceway and the outer raceway.