Tuning the mechanical properties of copper by changing deformation temperature and recrystallization fraction

In order to reveal the effects of cryogenic temperature on the relationship between mechanical properties and recrystallization percentage, the tensile mechanical behaviors of partial recrystallized copper have been investigated by tensile test at 293 K and 77 K, respectively. It is found the yield strength of copper maintains approximate linearity with recrystallization percentage at 77 K and 293 K. Microscopic observations manifested that the deformation twinning was not activated and dislocations slip still dominated plastic deformation at 77 K. Based on the proliferation and annihilation of dislocations, an exponent hardening model was employed to explain the simultaneous improvement of strength and ductility caused by cryogenic temperature.