Johnson-Cook model calibration for brittle materials under impact loads

In the assessment of parts subjected to impact loading, the current process relies on static analysis, which overlooks the significant influence of high strain rate on material hardening and damage. The omission of these effects hinders accurate impact simulations, limiting the analysis to comparative studies of two components and potentially misidentifying critical hot spot locations. To address these limitations, this study emphasizes the importance of incorporating the effects of high strain rate in impact simulations. By utilizing the Johnson-Cook material calibration model, which includes both material hardening and damage models, a more comprehensive understanding of material behavior under dynamic loading conditions can be achieved. The Johnson-Cook material hardening model accounts for the strain rate sensitivity of the material, providing an accurate representation of its behavior under high strain rate conditions. This allows for improved prediction of material response, particularly in terms of plastic deformation and flow stress. Additionally, the Johnson-Cook material damage model considers the progressive accumulation of damage and its influence on the material's failure behavior under impact loading. By incorporating this model, the simulation can accurately capture the initiation and propagation of fractures, providing a more realistic representation of the structural response. This study focuses on the calibration of the Johnson-Cook model for Brittle material and its application in predicting Knuckle failure at the tie rod arm location under impact loads. To validate the predictions of Knuckle failure at the tie rod arm location, the simulation results obtained using the calibrated Johnson-Cook model are compared with physical tests. A pendulum setup capable of delivering high-velocity impacts is utilized in the physical tests. The resulting data from the physical tests, including fracture patterns and impact behavior, are carefully recorded and compared with the simulation results. This study shows that a calibrated Johnson-Cook model is a reliable tool for simulating and predicting Knuckle failure in structures subjected to impact loading. The validation of the simulation results using physical tests adds credibility to the accuracy of the Johnson-Cook model and its suitability for predicting Knuckle failure in practical applications.