| 摘要 |
PROBLEM TO BE SOLVED: To improve wettability of a rolling element to a lubricant and to prolong the vibration life of a rolling bearing by forming at least the rolling element of a bearing ring and the rolling element from a ceramic obtained by adding at least aluminum oxide, ytterbium oxide and tungsten oxide as sintering auxiliaries to silicon nitride as a main component. SOLUTION: Plural balls 1 as rolling elements are made of an Si3N4-based ceramic, arranged between an inner ring 2 and an outer ring 3 made of high- carbon chromium bearing steel to constitute a rolling bearing. Si3N4 of a main raw material is mixed with 10 wt.% of Al2O3, Yb2O3 and WO3 of sintering auxiliaries and sintered to give the balls 1. The rolling bearing is applicable to both a rolling bearing for supporting in the radial direction and a rolling bearing for supporting in the thrust direction. The amount of a lubricant such as oil, grease, etc., sealed can be reduced and prolongation in life can be actualized. The inner ring 2 and the outer ring 3 may be made of a stainless steel, a ceramic, etc. |
