Deformation Analysis of Boron/Aluminum Specimens by Moire Interferometry
SourceWhole-field surface deformations were measured for two slotted tension specimens from multiply laminates, one with 0° fiber orientation in the surface ply and the other with 45°orientation. Macromechanical and micromechanical details were revealed using high-sensitivity moire interferometry. Although global deformations of all plies were essentially equal, numerous random or anomalous features were observed. Local deformations of adjacent 0° and 45° plies were very different, both near the slot and remote from it, requiring large interlaminar shear strains for continuity. Shear strains were concentrated in the aluminum matrix. For 45° plies, a major portion of the deformation was by shear; large plastic slip of matrix occurred at random locations in 45° plies, wherein groups of fibers slipped relative to other groups. Shear strains in the interior, between adjacent fibers, were larger than the measured surface strains.