The purpose of this paper is to evaluate the contact performance of traditional all-steel bearings and hybrid rolling bearings, as well as their variation patterns.
This paper focuses on traditional all-steel cylindrical thrust roller bearings and hybrid ceramic thrust roller bearings. Using Hertzian contact theory, the contact stress calculation formulas for steel-steel and steel-ceramic line contacts are derived. A finite element analysis model of the bearings is developed to evaluate and analyze the contact stress and von Mises stress distribution patterns for both types of bearings. The contact stress results from the finite element analysis are compared and validated against values derived from Hertzian contact theory. Additionally, the effects of load, roller radius and roller material on the contact stress were discussed, and the main measures for reducing edge stress concentration were also examined.
Significant stress concentration and edge effects are observed at the ends of the rollers in both bearing types. The contact stress in hybrid bearings is generally higher than that in full-steel bearings. Additionally, the contact areas at the roller edges in hybrid bearings are more susceptible to spalling damage and the formation of micro-cracks, rendering them the weak points for fatigue failure. The roller radius serves as an effective geometric parameter for regulating peak contact stress under axial loading. As the roller elastic modulus increases, both maximum contact stress and von Mises stress rise monotonically due to reduced elastic compliance and a smaller effective contact area. When the roller is made of c-BN material, the maximum contact stress increases by 34.2% and the von Mises stress increases by 58.7% compared with zirconia ceramic. Proper profiling and stiffness tailoring can smooth the stress distribution on the washer and reduce the stress concentration tendency at the roller ends. In addition, the coupling optimization (geometric cutting + elastic composite flexibility) is more effective in reducing the equivalent stress.
This study provides valuable references for the design and fatigue life validation of hybrid ceramic bearings.
