Abstract: Aimed at a secondary system on the coupling damage of sliding wear and contact fatigue in linear contact， combining the modified Archard’s wear model， the critical plane method and the virtual crack extension method， an analysis model of the coupling damage between sliding wear and contact fatigue is developed. Based on the Morris sensitivity method， the contribution ratio of contact fatigue sensitivity is established. Furthermore， a life prediction method of the coupling damage of both sliding wear and contact fatigue is proposed based on the sensitivity contribution ratio. The results show that the coupling damage life is obviously less than the single damage life. The sensitivity of coupling damage is significantly affected by contact pressure， contact width and curvature radius， and the contribution ratio of contact fatigue damage is basically linear with key parameters. The coupling damage life prediction result is in good agreement with the calculation result， which verifies the usability of the prediction model for coupling damage life.

Key words: coupling damage; sliding wear; contact fatigue; sensitivity; prediction method