利用轴承球三点接触纯滚动疲劳试验机,以氮化硅陶瓷球作为被试球,根据Hertz弹性接触理论,针对于纯滚动接触状态,分析了试验机滚轮直径、凹弧直径、陪试滚子直径对被试球三点最大接触应力相对差值的影响;数值结果表明:当滚轮半径为25mm,凹弧半径为40mm,陪试滚子半径为12.5mm,被试球半径变化范围为4.25mm―10.5mm时,三接触点的应力相对差值小于1%。适当减小被试球半径变化范围,能够降低三接触点的应力相对差值。三接触点的应力相对差值越小,其对被试球的测试寿命影响越小。 According to the Hertz elastic contact theory, according to the state of pure rolling contact, the roller diameter, the concave arc diameter of the testing machine, The results show that when the roller radius is 25mm, the concave arc radius is 40mm, the radius of the escrow roller is 12.5mm, the radius of the test ball varies from 4.25 mm-10.5mm, the three points of the relative stress difference less than 1%. Appropriate to reduce the test ball radius range, can reduce the relative stress of the three contact points. The smaller the relative difference of the stresses at the three points of contact, the smaller the impact on the test life of the tested ball.