The change law of stiffness of ceramic ball bearing is similar to that of all-steel bearing, but the change is relatively gentle.
Under the positioning preload, the centrifugal force of the inner ring and the ball, as well as the effect of frictional heat, increase the contact load of the inner and outer rings, while the contact angle of the outer ring decreases, and the contact angle of the inner ring increases, so that the contact stiffness increases, but the contact between the outer ring and the outer ring increases. The decrease in angle moderates the increase in axial and angular stiffness.
Under constant pressure and preload, the centrifugal force of the ball increases, which increases the contact load of the outer ring and reduces the contact angle at the same time. Since the inner and outer rings allow axial displacement, the contact load of the inner ring is basically unchanged, but the contact angle increases. Thermal displacement and centrifugal displacement have little effect on the contact load and contact angle of the inner and outer rings.
Although the normal contact stiffness of the outer ring increases, the normal contact stiffness of the inner ring remains basically unchanged. The result of the series action increases the radial stiffness, but not much, while the decrease of the contact angle of the outer ring makes the axial and angular stiffnesses significantly reduced.
Under the positioning preload, the rigidity of the ceramic ball bearing is lower than that of the all-steel bearing, while under the constant pressure preload, the rigidity of the ceramic ball bearing is greater than that of the all-steel bearing.
Under the positioning preload, the contact load of the all-steel bearing is more than double that of the ceramic ball bearing. Although the elastic modulus of the ceramic ball is high, the stiffness of the all-steel bearing is greater than that of the ceramic ball bearing. Under constant pressure and preload, the contact load of the inner ring does not change much, and the high elastic modulus of the ceramic ball makes the stiffness of the ceramic ball bearing greater than that of the all-steel bearing.