Analysis of hot deformation behavior of TB9 titanium alloy after friction correction and establishment of processing map

Abstract

The hot compression tests of TB9 titanium alloy sample were carried out on Gleeble-1500 thermal simulator at the temperature range of 750-1000 ℃ and the strain rate range of 0.01-10 s−1. The stress-strain curves obtained by the experiment were subjected to friction correction and the processing map was drawn according to the corrected stress-strain curve .The results show that the stress-strain curve after friction correction is obviously lower than that before correction, and the stress difference between them increased with the increase of strain. The corrected stress−strain curve is \begin{document}$ \sigma {\text{ = }}\frac{{\arcsin h{{[\frac{{\dot \varepsilon \exp (\frac{Q}{{RT}})}}{A}]}^{\frac{1}{n}}}}}{\alpha } $\end{document}，and can used to predict the stress of TB9 titanium alloy under different strain rates at 750 ℃ to 1000 ℃. Instable deformation of TB9 titanium alloy leads to localize the deformation bands which is about 45° to the compression direction appeared, resulting in the inhomogeneous microstructure. Stable deformation during hot working in suitable process window can bring dynamic recrystallization and recovery in the alloy, which can improve the microstructure and properties of the alloy. According to the processing map, the suitable thermal deformation process parameters of TB9 titanium alloy are obtained as follows: deformation temperatures of 850-1000 ℃ at deformation rates of 0.01-1 s−1.

Keywords

• tb9 titanium alloy
• hot compression
• processing map
• stress–strain curve correction