Creep Failure Estimation of Nickel-Based Superalloys Using Unified Mechanics Theory (UMT)

Failure modes of alloys such as creep failure, fatigue, fracture, etc., are generally treated as separate problems and are modelled separately using either empirical equations or based on the physics of individual failure mechanisms. However, modeling failure under the simultaneous action of different failure modes has been challenging for the engineering community. Unified Mechanics Theory (UMT) is an entropy-based failure model that uses entropy generated as a common “currency” to sum and determine the extent of damage and failure due to different modes. In this work, we use UMT to investigate creep failure in DZ125 nickel-based superalloy. We use the experimental data to calibrate and predict the failure strains (strain at the end of secondary creep) due to creep at different creep loads and temperatures.