A rolling bearing includes an inner ring, an outer ring, and a plurality of balls interposed between the inner ring and the outer ring. The inner ring and the outer ring are made of stainless steel. A raceway surface with which the ball is in rolling-contact in each of the inner ring and the outer ring and is a superfinished surface and a coating layer made of a solid lubricating film is formed on the superfinished surface.

A rolling bearing includes an inner ring, an outer ring, and a plurality of balls interposed between the inner ring and the outer ring. The inner ring and the outer ring are made of stainless steel. A raceway surface with which the ball is in rolling-contact in each of the inner ring and the outer ring and is a superfinished surface and a coating layer made of a solid lubricating film is formed on the superfinished surface.

A gear shaft allows a ceramic bearing to be used in environments where gear steel is desirable for driving a gear. The gear shaft includes a gear region and a bearing region. A bearing can be disposed about the bearing region of the gear shaft. A gear can be disposed about the gear region of the gear shaft. The bearing includes a ceramic material. The gear region of the gear shaft includes gear steel, whereas the bearing region of the gear shaft includes a bearing-region material that has a coefficient of thermal expansion (CTE) that is close to the CTE of the ceramic material.

A gear shaft allows a ceramic bearing to be used in environments where gear steel is desirable for driving a gear. The gear shaft includes a gear region and a bearing region. A bearing can be disposed about the bearing region of the gear shaft. A gear can be disposed about the gear region of the gear shaft. The bearing includes a ceramic material. The gear region of the gear shaft includes gear steel, whereas the bearing region of the gear shaft includes a bearing-region material that has a coefficient of thermal expansion (CTE) that is close to the CTE of the ceramic material.