| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a roller bearing (hybrid bearing) having excellent seizure resistance as the one having a rolling element composed of a spherical body made of silicon nitride and an inner ring and an outer ring composed of a steel material. <P>SOLUTION: The inner ring 1 and outer ring 2 of a roller bearing are made of SUJ2. The ball 3 made of silicon nitride is obtained by a sintering stage and a ball mill stage. In the sintering stage, raw material powder comprising silicon nitride as the main component, and comprising alumina (Al<SB>2</SB>O<SB>3</SB>) and yttria (Y<SB>2</SB>O<SB>3</SB>) as sintering aids, and in which the content of titanium oxide (TiO<SB>2</SB>) is ≤1,000 ppm is molded into a prescribed shape, and is thereafter sintered. In the ball mill stage, the raw material powder is charged inside a mill pot of a planetary ball mill, the planetary ball mill is operated, centrifugal force accompanying revolution generated in the mill pot and centrifugal force accompanying rotation are applied to the spherical bodies so as to collide the spherical bodies each other, further, the spherical bodies are collided against the inner wall of the mill pot so as to increase the residual stress in the surfaces of the spherical bodies. <P>COPYRIGHT: (C)2011,JPO&INPIT |
