A stress-related model for reliability lifetime estimation of ACA joints based on accelerated failure date

The model based on the accelerating aging tests, such as 85°C/85%RH, are usually used to estimate the reliability and MTTF of ACA joints in their normal working condition. Experiences show that it will lead inaccurate results if the influence of temperature level on reliability degradation is not considered. In this paper, the effect of the temperature level (namely working stress, denoted by s) on reliability of ACA joints is studied based on several accelerated failure experiments, and the potential relationship between the temperature stress and the lifetime of joints is revealed. After that, a stress-related lifetime prediction model is proposed, by which the mechanical reliability and the mean-time-to-failure (MTTF) of joints, working under any temperature condition, can be estimated. Numerical calculations have been done, and the results show that the MTTF of joints differ greatly if they experience different working temperature. This paper presented an applicable solution to estimate ACA joints´ lifetime under actual working stress by use of accelerating aging tests.