Recovery experimental techniques of tensile impact

Abstract

Based on loading-unloading test, tensile impact recovery experimental techniques have been developed to obtain the isothermal stress-strain curves of materials under high strain rates. The thermal softening effect can be decoupled by comparing the isothermal stress-strain curves with the adiabatic stress-strain curves at the same strain rate. In the present paper, recovery experiments of brass have been carried out on a self-designed rotating disk tensile impact apparatus. According to the parabolic strain hardening power-law thermo-viscoplastic constitutive model, strain hardening parameter, strain rates strengthening parameter and thermal softening synthetical parameter have been decoupled from experimental results. Furthermore, from these parameters, one can determine the theoretical isothermal curves and adiabatic curves at high strain rates well-coinciding the experimental results respectively. It indicates that the recovery experimental techniques of tensile impact are effective and reliable and are important means for the study of thermo-mechanical coupling. The experimental results also reveals that brass is a typical thermo-viscoplastic material.