Role of Statistical Vis-a-vis Physics-of- Failure Methods in Reliability Engineering

Traditionally the statistical or more specifically probabilistic methods form the basic framework for assessing the reliability characteristics of the components. However the recent trend for predicting the reliability or life of the component involves application of physics-offailure methods. This rather new approach is finding wider application as it is based on basic fundamentals of science and thereby provides an improved framework to understand the failure mechanism. Since accelerated testing of component forms part of this approach, the prediction of time-to-failure of the components is more accurate compared to the existing methods which depends only historical data and its evaluation using probabilistic methods. The new approach is all the more relevant when it comes to assessment of reliability of new components as the traditional probabilistic approach is not adequate to predict reliability of new components as it depends on historical data for prediction of reliability. In view of the above this paper investigates the role of statistical or probabilistic approach and physics-of-failure approach for reliability assessment of engineering components in general and electronics components in particular.