Roller bearings are widely used in various rotating machineries. A main failure mode of the roller bearings is the subsurface crack due to the contact fatigue, which can produce large spalling. An investigation of the contact characteristics of the bearings with the subsurface crack may be helpful for the incipient fault detection, which were not reported in the previous works. To overcome this problem, this study presents a finite element model to study the effects of the horizontal and slant subsurface cracks on the contact characteristics in a roller bearing. The relationship between the contact deformation and crack sizes (length, depth, and slope angle) is obtained, as well as that between the contact zone width and crack sizes. The mathematic relationship between the contact characteristics and crack sizes is obtained by using a polynomial fitting approach. Note that the crack length, depth, and slope angle will affect the contact characteristics of the bearing. The results provide that the established approach can give a useful numerical method for analyzing the contact characteristics of a roller bearing with the horizontal and slant subsurface cracks.

滚动轴承广泛用于各种旋转机械中。滚动轴承的主要失效模式是由于接触疲劳引起的表面裂纹，这会产生较大的剥落。研究轴承与表面下裂纹的接触特性可能有助于早期故障的检测，这在先前的工作中并未得到报道。为了克服这个问题，本研究提出了一个有限元模型来研究水平和倾斜的地下裂纹对滚动轴承接触特性的影响。获得了接触变形和裂纹尺寸（长度，深度和倾斜角度）之间的关系，以及接触区宽度和裂纹尺寸之间的关系。接触特性和裂纹尺寸之间的数学关系是通过使用多项式拟合方法获得的。请注意，裂纹的长度，深度和倾斜角度会影响轴承的接触特性。结果表明，所建立的方法可以为分析滚动轴承表面水平和倾斜表面裂纹的接触特性提供有用的数值方法。