利用 Gleeble?3800热模拟试验机对 beta C 钛合金进行等温压缩试验，研究其在β相区的热变形行为。得到了描述热变形行为的本构方程，获得了真应变为0.7时的加工图。采用光学显微镜、扫描电子显微镜和电子背散射技术对变形显微组织进行表征。结果表明：流变应力随着应变速率加快而增大，随着试验温度的升高而减小。计算得到的表观激活能为167 kJ/mol，接近β钛的自扩散激活能。加工图和显微组织观察表明在温度为900~1000°C和变形速率为0.1~1 s?1的区间存在一个动态再结晶区。加工图显示，当变形速率大于1.7 s?1时，beta C 钛合金发生不稳定变形。Beta C 钛合金在动态再结晶区变形后，经合适的热处理，显微组织可以被优化。
The hot deformation behavior of beta C titanium alloy in β phase field was investigated by isothermal compression tests on a Gleeble?3800 thermomechanical simulator. The constitutive equation describing the hot deformation behavior was obtained and a processing map was established at the true strain of 0.7. The microstructure was characterized by optical microscopy (OM), scanning electron microscopy (SEM) and electron back-scattered diffraction (EBSD) technique. The results show that the flow stress increases with increasing strain rates, and decreases with increasing experimental temperatures. The calculated apparent activation energy (167 kJ/mol) is close to that of self-diffusion in β titanium. The processing map and microstructure observation exhibit a dynamic recrystallization domain in the temperature range of 900?1000 °C and strain rate range of 0.1?1 s?1. An instability region exists when the strain rate is higher than 1.7 s?1. The microstructure of beta C titanium alloy can be optimized by proper heat treatments after the deformation in the dynamic recrystallization domain.
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