The dynamic tensile behaviors of a newly developed Ti-6 Al-2 Sn-2 Zr-3 Mo-1 Cr-2 Nb-Si alloy(referred as TC21 in China) over a wide range of strain rates from quasi-static to dynamic regimes(0.001-1 200 s-1) at diff...The dynamic tensile behaviors of a newly developed Ti-6 Al-2 Sn-2 Zr-3 Mo-1 Cr-2 Nb-Si alloy(referred as TC21 in China) over a wide range of strain rates from quasi-static to dynamic regimes(0.001-1 200 s-1) at different temperatures were experimentally investigated. A split Hopkinson tension bar apparatus and a static material testing system were utilized to study the stress-strain responses under uniaxial tension loading condition. The experimental results indicate that the tensile behavior of TC21 titanium alloy is dependent on the strain rate and temperature. The values of initial yield stress increase with increasing strain rate and decreasing temperature. The effects of strain rate and temperature on the initial yield behavior are estimated by introducing two sensitivity parameters. The phenomenological-based constitutive model, Johnson-Cook model, is suitably modified to describe the rate-temperature dependent constitutive behavior of TC21 titanium alloy. It is observed that the modified model is in good agreement with the experimental data subjected to the investigated range of strain rates and temperatures.展开更多
Ribbons of the two-phase titanium alloy were fabricated by single-roller rapid solidification technique,and aged at high temperature. The microstructure of ribbon samples were characterized with X-ray diffractometer(X...Ribbons of the two-phase titanium alloy were fabricated by single-roller rapid solidification technique,and aged at high temperature. The microstructure of ribbon samples were characterized with X-ray diffractometer(XRD) and environmental scanning electron microscope(ESEM). The microstructures of the alloy are composed of α phase and supersaturated β phase,and X-ray diffraction results show that all peaks of the α and β phases shift slightly to smaller angles,which can be explained by the disordering growth pattern caused by the rapid solidification process. After aging at 960 ℃ in vacuum,the ribbon is composed of homogeneous α phase and β phase.展开更多
基金Funded by the National Natural Science Foundation of China Academy of Engineering Physics and Jointly Set up “NSAF” Joint Fund(No.U1430119)
文摘The dynamic tensile behaviors of a newly developed Ti-6 Al-2 Sn-2 Zr-3 Mo-1 Cr-2 Nb-Si alloy(referred as TC21 in China) over a wide range of strain rates from quasi-static to dynamic regimes(0.001-1 200 s-1) at different temperatures were experimentally investigated. A split Hopkinson tension bar apparatus and a static material testing system were utilized to study the stress-strain responses under uniaxial tension loading condition. The experimental results indicate that the tensile behavior of TC21 titanium alloy is dependent on the strain rate and temperature. The values of initial yield stress increase with increasing strain rate and decreasing temperature. The effects of strain rate and temperature on the initial yield behavior are estimated by introducing two sensitivity parameters. The phenomenological-based constitutive model, Johnson-Cook model, is suitably modified to describe the rate-temperature dependent constitutive behavior of TC21 titanium alloy. It is observed that the modified model is in good agreement with the experimental data subjected to the investigated range of strain rates and temperatures.
基金Projects(0552nm028 04DZ05616) supported by Shanghai Science and Technology Committee
文摘Ribbons of the two-phase titanium alloy were fabricated by single-roller rapid solidification technique,and aged at high temperature. The microstructure of ribbon samples were characterized with X-ray diffractometer(XRD) and environmental scanning electron microscope(ESEM). The microstructures of the alloy are composed of α phase and supersaturated β phase,and X-ray diffraction results show that all peaks of the α and β phases shift slightly to smaller angles,which can be explained by the disordering growth pattern caused by the rapid solidification process. After aging at 960 ℃ in vacuum,the ribbon is composed of homogeneous α phase and β phase.