Modeling and inverse identification method for the characterization of elastic-plastic contact behavior during flat punch indentation

In this work, an inverse identification method is developed for the experimental characterization of the elastic- plastic contact in indentation problem. The method consists of a modeling procedure and an identification procedure. In the modeling, a discrete interfacial stress model is developed and the 2D frictional flat but round punch condition (of which frictionless, sharp corner contact is a special case) is formulated. Only the tendencies of stress distributions are required to be constrained in the model which can highly increase the scope of application. In the identification, an alternative optimization scheme is proposed in which the contact parameters can be inversed by matching the modeled displacement to the experimental data. A displacement based yield criterion is developed so the plastic domain can be recognized without solving the stress or strain. The proposed method can characterize all of the contact parameters only by using the easy-acquired displacements. Simulation and experiments show that the proposed method can accurately characterize the contact from noisy measurements.

Automated summary

In this study, an inverse identification method is developed to characterize the elastic-plastic contact in indentation problem. The method utilizes a discrete interfacial stress model and an alternative optimization scheme to model and identify the contact parameters accurately.