PSD Analysis to Model Fretting Wear Failure

Can a random vibration PSD analysis be used to model fretting wear failure?

No. Fretting wear is material removal due to small oscillatory motion between two butting components. A non-linear FE (Finite Element) analysis is required. PSD is a linear analysis in the frequency domain. Wear due to oscillatory motion can be simulated in the time domain using the wear material model. The approach is explained in Chapter 43 of the Technology Demonstration Guide (Chapter 43: Contact Surface Wear Simulation (ansys.com)).

If the loading is specified as a PSD, it can be converted into the time domain, but the duration of the time domain signal may be very long. Thus, ensuring time-based, nonlinear wear contact analysis may be very computationally expensive. To minimize that expense, fretting wear simulations are often considered in three separate stages: contact model, crack initiation, and crack propagation.