航天医学与医学工程

碳化硅滑动轴承的长寿命和高可靠性对于航天器动力装置长期正常工作至关重要。针对某输送泵滑动轴承组合体在使用过程中出现破裂现象，本文从受力特性和温度膨胀效应角度进行分析，提出一种基于温度系数补偿的结构优化设计方案。研究表明，轴承破裂的主要原因是温升条件下轴承与金属转子存在膨胀系数差异，导致轴承轴向松动。此外，轴承与销钉之间的间隙及摩擦副润滑不稳定，进一步加剧了轴承的失速和销钉撞击，最终引发裂纹和局部崩裂。通过优化轴承结构并采用橡胶垫进行扭矩传递，可成功解决这一问题。改进后的结构在台架试验中表现出高可靠性和稳定性，为类似极端工况下的轴承设计提供了重要的理论和技术参考。

The long service life and high reliability of SiC sliding bearings are crucial for the long-term normal operation of aerospace power equipment. In response to the fracture phenomenon observed in the sliding bearing assembly of a certain delivery pump during operation, this paper analyzes the issue from the perspectives of stress characteristics and thermal expansion effects, proposing a structural optimization design method based on temperature coefficient compensation. The research indicates that the primary cause of bearing fracture is the difference in thermal expansion coefficients between the bearing and the metal rotor under elevated temperatures, leading to axial loosening of the bearing. Additionally, the gap between the bearing and the pin, combined with unstable lubrication of the friction pair, exacerbates bearing stalling and pin impact, ultimately causing cracks and localized chipping. By optimizing the bearing structure and employing a rubber pad for torque transmission, this issue has been successfully resolved. The improved structure demonstrated high reliability and stability in bench tests, providing important theoretical and technical references for the design of bearings under similar extreme operating conditions.