This report describes the development of forward and inverse modeling techniques capabilities for the resonances of components made of nickel-based (Ni-base) superalloys. These modeling techniques enable PCRT to evolve beyond its historically data-driven approach. RUS/PCRT applications have required large amounts of empirical data in the form of measured resonance frequencies, but the conditions of interest are not always available in sample populations. Forward modeling enables the prediction of resonance frequency changes in response to material conditions, geometric variations and defects of interest. Inverse modeling enables the determination of material state from measured or modeled resonance frequencies.