Numerical analysis of uniaxial strain ratcheting of conductive adhesives

Under the condition of uniaxial strain(Amplitude is plusmn0.025%), the elastic-plastic finite element method was used to analyze the bonding of conductive/copper wire. The result shows that the plastic strain of X and Y direction is mainly occurred at two positions: one is at the left arc side; the other is at the right arc side of the department. The maximum value of the von Mises equivalent stress occurs near the point outside the left arc as the strain cycle process. The peak value of von Mises equivalent stress in epoxy adhesive was higher than that in the ASA acrylon adhesive (91.1 MPa to 59.5 MPa). However, because the former has a higher yield strength, and therefore conductive epoxy adhesive failure is not easy.