Titanium Ta2 Dynamic Mechanical Properties Of Anisotropic Microstructure Observed Under High Strain Rate

The ansitropy of dynamic behavior of textured polycrystals sheets of pure titanium were investigated by means of Instron apparatus and Split-Hopkinson pressure bar technology respectively.Cylindrical and hat-shaped specimens of texured sheets,cut with the cylinder axis along the rolling direction(RD),transverse direction(TD),normal direction(ND)and the 45°direction(RD-45°)from rolling direction lyifig in the rolling plane,were compressed at quasistatic and dynamics deformation.The microstructures and microhardness of the specimens were observed and measured.The results show:The quasistatic and dynamical compressive mechanical properties show anisotropy.The yield strength of rolled pure titantyim for the ND direction is the most strongest,the strength for the TD direction is the second.The diffencec between the RD and RD-45°directions is very little.The yield strength of annealed pure titantyim for the ND direction is the most strongest,the TD direction is the second,the RD-45°direction is the third,the RD directions is the minimum.The dynamic forced-shear behavior experimental result show both rolled and annealed pure titanium sheets show anisotropy:the yield strength and flow stress of the ND direction is the maximum,the TD direction is the second,the RD-45°direction is the third,the RD direction is the minimum.The adiabatic shear sensitivity for different directions has the same rule.The microstuctural results show that the adiabatic shear bands of the rolled titanium sheet for different directions are wider than the annealed titanium sheet.The adiabatic shear band in the ND direction is the widest and in the RD is the thinnest at the same state.They are consistent with the tendency of peak shearing stress.