Decoupling Thermal and Electrical Effect in an Electrically Assisted Uniaxial Tensile Test Using Finite Element Analysis

摘要

Application of intermittent electric pulses during uniaxial tensile test changes the mechanical behavior owing to electroplastic effect. The electric current increases the temperature of the specimen due to Joule heating. It is, therefore, necessary to decouple the thermal effect from the overall behavior to understand the contribution of electric current in the mechanical behavior. In the present work, an electro-thermo-mechanical finite element study of an electrically assisted uniaxial tensile test of Al5052 alloy is performed to isolate the thermal effect. The simulated results yielded the thermal effect due to the electric current. By comparing the experimental and simulated results, the contribution of electric current is decoupled from that of thermal effect. It is found that the thermal component contributes significantly to the instantaneous stress drop and long-range permanent softening observed in experiment. The electric current, in addition to the instantaneous stress drop and permanent softening, affects the reloading behavior. The present work can be utilized to develop simpler constitutive models for the mechanical behavior of metals subjected to pulsed electric current.