Effect of sample geometry on the macroscopic shear deformation of the titanium alloy Ti-10V-2Fe-3Al subjected to quasi-static and dynamic compression-shear loading

We investigate the evolution of shear bands in a Ti-10V-3Fe-2Al alloy with three different initial microstructures: solution-annealed v-titanium, v-titanium with primary a-phase precipitates as well as a condition with primary and secondary a-phase precipitates. Quasi-static and dynamic testing of compression-shear specimens with strain rates of 10-3 s-1 and 102 s-1 is performed at room temperature. The influence of two different sample geometries on the macroscopic shearing tendency is investigated: samples with a cylindrical cross section and samples with a square cross section. The results of digital image correlation and the nominal stress-strain behavior under quasi-static and dynamic loading indicate a stronger localization tendency of the aged conditions with additional a-phase precipitates compared to the solution- annealed pure v-condition. Our results also demonstrate that compression-shear testing with samples with a square cross-section reduces facet loss, increases the resolution even at high strain rates and therefore allows to analyze strain distributions during shear band formation and propagation with higher accuracy.