The electromechanical behavior of carbon fiber reinforced polymer (CFRP) is critical for their structural self-sensing. In this study

the tensile electromechanical behaviors of open-hole 3D angle-interlock woven CFRP at different off-axis angles (0°

45°

60°

and 90°) were investigated with four-probe method and digital image correlation (DIC) technique. The effect of off-axis angles on the electromechanical performance of the composites was systematically examined. The results indicate that significant off-axis angle dependence in tensile properties. Axial specimens (0°

90°) demonstrate higher tensile strength and lower fracture strain

with carbon fiber yarns serving as the primary load-bearing components and fiber pull-out as the dominant failure mode. In contrast

off-axis specimens (45°

60°) display nonlinear deformation behavior

with resin matrix transferring most loads

while matrix cracking and interfacial debonding emerge as principal damage mechanisms. The electromechanical behavior of the composite exhibits significant off-axis angle dependence

with both current density and electrical potential distribution demonstrating notable angular correlation. Yarn conduction and interfacial contact conduction dominate the electrical conduction mechanisms in axial and off-axis specimens

respectively. The axial specimens show a resistance variation of less than 10% before fracture

whereas the offaxis specimens exhibit a resistance change exceeding 100% prior to final failure.