(中南大學(xué) 材料科學(xué)與工程學(xué)院，長沙 410083)
摘 要:
關(guān)鍵字: TC16鈦合金；動態(tài)本構(gòu)關(guān)系；Hopkinson壓桿試驗；應(yīng)變速率；溫度
（School of Materials Science and Engineering, Central South University, Changsha 410083, China）
Abstract:The true stress—true strain curves of Ti-3%Al-5%Mo-4.5%V alloy with a wide range of strain rates were investigated under uniaxial quasi-static tension and uniaxial dynamic compression respectively with Instron 8032 test machine and the split Hopkinson bar. A new method incorporating the stress—strain curve of Ti-3%Al-5%Mo-4.5%V alloy was proposed for determining the parameters based on Johnson-Cook model easily and avoiding the estimation of adiabatic temperature rising. The Johnson-Cook dynamic constitutive relationship for Ti-3%Al-5%Mo-4.5%V alloy was obtained. The results show that the true stress increases with increasing strain rate, while decreases with increasing temperature. Under the condition of high strain rate of 105/s and temperature above 673 K, the true stress is even less than that under quasi-static condition. Good agreement is obtained between the model prediction and the experimental stress—strain curves for Ti-3%Al-5%Mo-4.5%V alloy under both quasi-static and dynamic loadings.
Key words: TC16; dynamic constitutive relationship; SHPB; strain rate; temperature
