Experimental and numerical investigation on the macroscopic mechanical behavior of shape memory alloy hybrid composite with weak interface

This paper presents an experimental and numerical investigation into the macroscopic mechanical behavior of shape memory alloy hybrid composites (SMAHCs) subjected to quasi-static loading taking into account of weak interface effect and damage evolution. SMA fiber reinforced hybrid laminates were fabricated by vacuum assisted resin injection (VARI). Scanning electron microscopy was used to evaluate the quality of SMA-matrix interface. Uniaxial tensile tests were performed to study the effects of weak interface on the effective modulus of hybrid composite. Failure morphology was discussed based on the observation using digital HF microscope. Owing to the embedding of SMA fiber, the material exhibited a bilinear mechanical behavior, and the overall stiffness of composite at the second stage was lower on average 32.7% than that of the first stage. Ultimate strength was improved by 3.4% for the three-SMA-fiber composite, and rupture elongation was slightly decreased (∼0.1%). A script program was developed to generate the hybrid composite model by using ANSYS Parameter Design Language (APDL). Uniaxial tensile test was simulated using finite element method to study the macroscopic behavior of hybrid composite based on a bilinear cohesive zone model (BCZM). The effects of embedded SMA fiber number and fiber ratio were respectively discussed.