High-temperature deformation behavior and prediction model of the columnar network 2.5 vol% TiBw/TA15 composites

To achieve high precision forming of the columnar network TiBw/TA15 composites, it is essential to accurately predict their flow stress during deformation. This study systematically analyzes the deformation behavior of the composite during high-temperature compression, confirming that its flow resistance decreases with increasing temperature and increases with increasing strain rate. It is observed that, even under external temperature control, transient temperature rise and heat dissipation caused by thermo-mechanical coupling effects during deformation lead to significant deviations between experimental data and the assumptions of ideal constitutive models. To address this issue, an integrated dual compensation approach incorporating both temperature and strain factors is applied to systematically modify the flow stress behavior. And the finite element method is employed for the first time to model and validate the classical peak stress constitutive model, a single strain-compensated model, and the proposed dual-compensation constitutive model for titanium matrix composites. The results indicate that the newly developed dual-compensation constitutive model exhibits superior predictive performance. Under typical hot deformation conditions, the maximum absolute stress deviation between predicted and experimental values is only 5.2 MPa, with a relative error of 3.8%. Compared to the classical peak stress model and the single strain-compensated model, the relative errors of the proposed model are reduced by 82.88% and 72.80%, respectively, significantly enhancing the accuracy of the constitutive description. This advancement considerably improves the adaptability of the model for TiBw/TA15 composites and provides an accurate simulation model for the iterative optimization of hot deformation process parameters.