Mechanical properties of anisotropic conductive film with strain rate and temperature

Stress relaxation test and uniaxial tensile test of anisotropic conductive film (ACF) were conducted on DMA-Q800. A nonlinear relaxation behavior of ACF was observed. The relaxation rate became large and the stress relaxation curves at different strains became close with the increase of temperature. The stress relaxation curves were strain independent near glassy transition temperature (Tg). Strain rate and temperature dependent nonlinear stress and strain curves were obtained. The tensile strength and Youngʹs modulus decreased with the increase of temperature, and specially were reduced more between 80 and 120 °C, however, ultimate strain of ACF increased with the rise of temperature. A nonlinear viscoelastic constitutive model of ACF was proposed to simulate stress relaxation under different strains. It showed good agreement between experimental data and simulation.