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The most common used warranty prediction method at component level (non-repairable system) is called Weibull analysis. In Weibull analysis, failure time is assumed to follow a certain distribution such as Weibull, and time is the only predictor in the model for predicting percentage of failures. However, other variables such as design variables, manufacturing parameters, and field use condition also affect warranty. These variables should be considered in the prediction. In this paper, a multiple regression approach is proposed to predict warranty failures of a solenoid switch by considering multiple factors that affect the warranty. A single failure mode caused by fatigue is studied. The failure is caused by out of GD&T (Geometric Dimension and Tolerance) specs. These GD&T variables together with component operation time are used as predictors in the model. The final model is established by integrating physics of failures with statistical analysis results.

Two popular critical plane models developed by Fatemi-Socie and Smith-Watson-Topper were derived from the experimental observations of the nucleation and growth of cracks during loading. The Fatemi-Socie critical plane model is applicable for the life prediction of materials for which the dominant failure mechanism is shear crack nucleation and growth, while the Smith-Watson-Topper model, for materials that fail predominantly by crack growth on planes perpendicular to the planes of maximum tensile strain or stress. The two critical plane models have been validated primarily by in-phase and 90° out-of-phase loading, and few, on the complex, non-proportional loading paths. A successful critical plane model should be able to predict both the fatigue life and the dominant failure planes. However, some experimental studies indicate the 304 stainless steel has the two possible failure modes, shear and tensile failure dominant, depending on the loading mode and stress and strain states.