Abstract: As for the problem of life prediction of mechanical components with multiple failure modes, the failure logistical relationship between the component and its failure modes is analyzed, and the method for describing the failure behavior of component with multiple failure modes is studied. Then, with the continuous variable and discrete variable as the life parameter respectively, the life probability distribution models of component with multiple failure modes are developed. The cumulative distribution function and probability density function of life of component are derived and the models of reliability, failure rate model and mean time to failure of component are also derived. The life probabilistic characteristics of component with multiple failure modes and the rules that the reliability and failure rate changes are studied. The results show that for the components with multiple failure modes, the failure probability of component is more than the failure probability corresponding to each one of its failure modes, and as the life parameter increases the failure probability density of component presents the rule that it is high in the early failure period, and then decreases first and after that increases, finally decreases. And the mean time to failure of component is less than that corresponding to each one of its failure modes

Key words: failure behavior, life prediction, multiple failure modes, probability distribution characteristic, mechanical components