A Review of Multiaxial Fatigue Life Predictions Methods and a Novel Graphical User Interface

Critical components in machines for power generation, aerospace, and other heavy-duty applications are exposed to multiaxial stress histories that render the life prediction process more challenging. Multiple life estimation models have been developed over the last 50 years, each differing by parameters such as: approach, processing time/complexity, accuracy, parameter set, calibration, connection to microstructurally observed behavior, and more. A critical review of the various methods used in the current study is provided. A new graphical user interface is presented as a tool to support life prediction computations, model selection, and parameter calibration. Both stress- and strain-based approaches can be used, and both single point and full-scale structural models can be considered. Consequently, the GUI accelerates the life prediction process for materials subject to multiaxial conditions without sacrificing accuracy by assigning the best life prediction methods. The GUI is able to intake a large set of multiaxial loading data and examine the data to provide the best parameters for the life prediction models along with critical points where failure might occur. For this current study, a compendium of data of Inconel 718 subjected to multiaxial fatigue at room temperature and 600 °C was used, with varying heat treatments, loadings, and life estimates.