APPLICATION OF THE DIGITAL IMAGE CORRELATION METHOD FOR DETERMINING TRUE STRESS-STRAIN CURVES OF COMMERCIALLY PURE TITANIUM UNDER DYNAMIC LOADING CONDITIONS

A new method of determining true stress-strain curves using digital image correlation was presented. It was applied to determine mechanical response of commercially pure titanium at wide range of strain rates. Image analysis makes possible to investigate necking during subsequent step of plastic deformation. Therefore it was possible to take into account real cross-section of the specimen and obtain true strain and stress values. Data obtained at dynamic loading conditions were analytically corrected to get quasi-isothermal curves. Finally, the proposed method was validated by comparison of experimental data with numerical simulation results of tensile tests.