Flow Behavior Analysis and Flow Stress Modeling of Ti17 Alloy in \({\varvec{\beta}}\) Forging Process

Isothermal compression tests are conducted using a thermomechanical simulator at a constant strain rate during deformation temperature range of 850 to 950 °C and strain rate range of 0.001-10 \({s}^{-1}\) to study the flow behavior of Ti17 alloy with initial basketweave microstructure in \(\beta \) forging process. The strain rate sensitivity exponent m and strain hardening exponent n are calculated, and the strain-compensated constitutive model of flow stress using hyperbolic sine-based Arrhenius model is constructed. The results show that the strain rate sensitivity exponent m is greater than 0.3 when the strain rate is low in the range of 0.001-0.01 \({s}^{-1}\), and reaches its maximum at 900 °C; the component is less than 0.3 at high strain rate range of 0.1-10 \({s}^{-1}\), and it is slightly lower at 850-900 °C compared with at 920-950 °C. The strain hardening exponent n monotonously decreases with the increase in true strain at strain rate of 0.001 \({s}^{-1}\), while for strain rate in the range of 0.01-10 \({s}^{-1}\), it decreases with the increase in strain when the true strain is less than 0.3 but does not show significant change when the true strain is greater than 0.3. The established strain-compensated flow stress constitutive model has high prediction accuracy with average absolute relative error (AARE) of 5.32% and correlation parameter R of 0.993. The model can thus be used to provide theoretical guidance for selecting \(\beta \) forging process parameters, and also provide the basic data for finite element simulation of \(\beta \) forging process of Ti17 alloy.