Patent ID: 6602360
Filing Date: 2003-08-05
Classification: C22C,F16C,Y10S

Abstract:
A rolling bearing comprising:a stationary ring; a rotary ring; and a plurality of rolling elements rotatably interposed between said stationary and rotary rings, at least said stationary ring is made of an iron-steel material containing alloying components of: 0.40% to 1.20% by weight of carbon (C); 0.7% to 2.0% by weight of at least one of silicon (Si) and aluminum (Al); 0.2% to 2.0% by weight of manganese (Mn); 0.1% to 3.0% by weight of nickel (Ni) and 3.0% to 9.0% by weight of chromium (Cr), where Cr-equivalent amount defined by following formula (1) is 9.0 wt % to 17.0 wt %, Cr-equivalent amount (%)=[Cr]+2[Si]+1.5[Mo]+5[V]+5.5[Al]+1.75[Nb]+1.5[Ti]â€ƒâ€ƒ(1) â€ƒin the formula, [Cr], [Si], [Mo], [V], [Al], [Nb] and [Ti] show containing percent (wt %) of Cr, Si, Molybdenum (Mo), Vanadium (V), Al, Niobium (Nb) and Titanium (Ti) in the iron-steel material, and wherein said at least said stationary ring has a rolling surface which is subjected to quenching and tempering and has hardness of HRC 57 or higher, wherein at least said stationary ring further comprises: at least one of V, Nb and Ti, while satisfying a condition that V&lE;2.0 wt %, Nb&lE;1.0 wt %, and Ti&lE;1.0 wt %, and wherein a maximum diameter of carbide existing in the rolling surface of at least said stationary ring is less than 10 &mgr;m, wherein average diameter of fine carbide existing in the rolling surface of at least said stationary ring is 71 to 475 nm, and wherein the average diameter is defined by (maximum diameter+minimum diameter)/2 (nm).