K. Line, G. Krishnan, M. Oja, W. Li, VEXTEC, Brentwood, TN; R. Tryon, VEXTEC Corporation, Brentwood, TN
Electronic prognostics is a growing field important to both military and commercial applications. When implemented, this capability will greatly enhance the maintenance management of platforms. Electronic prognostics require extensive use of physics of failure models to predict the remaining useful life of complex electronic failure modes. VEXTEC has developed a material-based physics of failure analysis tool for use in a variety of programs with aerospace OEMs. These techniques are far more accurate and versatile than traditional fatigue life analysis by using the grain and material properties for damage prediction. By modeling the stresses induced on interconnects by thermal and vibration forces, current damage estimates and remaining useful life can be calculated. The data required to drive these models uses measurands commonly available from electronic systems such as board temperature and loads induced by flight or operational conditions. The electronic circuit accelerated life test programs have shown excellent correlation between the predictions from material based physics of failure models and induced circuit board failures. VEXTEC’s probabilistic roll-up models of electronic component circuits and interconnects predict overall system reliability to provide the operator with useful information for managing vehicle maintenance.
Summary: Vibration and thermal models are used to predict the local conditions on electronic components. These conditions are used with microstructural material models to predict the probability of failure of the component. The models are validated with laboratory test.
