Interfacial stress transfer behavior of single-fiber composite under the effect of mechanical and thermal loading

The interfacial shear stress of a three dimensional freezing slice of single-fiber pullout resin matrix composites under the combined effect of pullout loading and thermal residual stress was studied using the three dimensional photo-elasticity and the finite element method. The results show that the value of the interfacial thermal residual stress reaches its peaks near the ends of the embedded fiber in the interface of the single-fiber and the matrix. The interfacial shear stress presents a parabolic distribution，and the transferring area mainly focuses on the region of the embedded top of the fiber where the stress reaches the critical point first，causing the debonding of the interface，and then the shear stress transfers along the embedded fiber. The effect of interfacial thermal residual stress on the interfacial shear stress reduces the stress concentration near the end of the embedded fiber，making the maximum of the interfacial shear stress increase.