21. Probabilistic Physics-of-Failure Approach in Reliability Engineering

This chapter describes an overview of the probabilistic physics-of-failure for applications to reliability engineering problems. As reliability engineering experts face situations where system and component reliability failure data are lacking or with the poor quality, a powerful modeling approach is to relay on the underlying processes and phenomena that lead to failures. Originally derived from chemistry, mechanics, and metallurgy, the processes that lead to failures are called failure mechanisms that include phenomena such as fatigue, creep, and corrosion. Physics-of-failure is an empirically based mathematical and analytical approach to modeling these underlying processes of failures. Due to limitations of information and test data available for the understanding of these processes, the PoF-based reliability should include formal accounting of the uncertainties. The physics-of-failure methods in reliability engineering that consider uncertainties lead us to the probabilistic physics-of-failure. This chapter covers some important analytical and practical aspects of the probabilistic physics-of-failure modeling, including some examples.