Abstract: In view of the lack of failure data, this paper constructs a failure model of conductive slip ring, and studies the reliability evaluation of slip ring mechanism by combining small-sample data processing method and randomness theory. First, considering the characteristics of slip ring in the thermoelectric multi-field coupling environment, heat transfer theory, Hertz theory and energy conservation law is applied to calculate multi-field coupling having the effect on the friction pair materials. Then the failure model of conductive slip ring friction pair under multi-field coupling is constructed combining with Archard model theory. The virtual augmentation method and boot-strap method with small samples are adopted to extend the simulation data and the reliability function before and after the expansion are obtained according to the distribution law of the characteristic amount of slip ring wear. In this paper, the reliability evaluation of the slip ring is verified by taking the characteristic parameters of the slip ring manufactured in a factory as an example. And the experiment results show that the reliability of the random failure threshold is more appropriate to the actual reality. The research shows that the proposed model and method can predict the reliability of the conductive slip ring reliably and it solves the problem that it is difficult to analyze the reliability of the conductive slip ring without the reliability data of the slip ring. The proposed method fills in the blank of the research on the reliability of the conductive slip ring.

Key words: Conductive slip ring, Wear failure model, Small-scale Sample, Reliability assessment, Failure threshold