Akademik Veri Yönetim Sistemi
26th International ESAFORM Conference on Material Forming, ESAFORM 2023, Krakow, Polonya, 19 - 21 Nisan 2023, cilt.28, ss.807-816
The aim of this study is to calibrate the parameters of the Johnson-Cook (JC) and modified Mohr-Coulomb (MMC) ductile failure models for Inconel 718 and predict the formability limit in the flow forming process using the aforementioned uncoupled damage models. Uniaxial tensile tests are performed on four different specimen geometries to cover a variety of stress states. A hybrid methodology combining finite element simulations and experimental findings is used to calibrate the JC and MMC damage models. The models are implemented in the finite element solver Abaqus using a user-defined subroutine. Results show that the calibrated models agree well with the experimental data in all tensile tests. In shear dominant loads, the MMC model is found to be more capable of showing accurate crack propagation. In flow forming simulations, a significant difference is observed between the JC and MMC models in the prediction of damage. Lode parameter-dependent damage models, such as the MMC, are found to be more suitable for the prediction forming limits in the flow forming process.