Theoretical and experimental investigation of the nonlinear behavior of angleplied boron/aluminum composites

Specimens from angleplied laminates of boron/aluminum composites were tested and the results analyzed. The specimens consisted of eight-ply symmetric layups and were loaded in tension at various angles to the 0 deg-ply direction. Stress-strain curves to specimen fracture were obtained. The analysis was performed using linear composite mechanics which includes residual stresses and a combined stress yield function. The results obtained indicate that angleplied boron/aluminum laminates exhibit a nonlinear stress-strain behavior to fracture. The residual stresses affect the initial and yield laminate properties. Linear composite mechanics is inadequate to predict the mechanical behavior of boron/aluminum angleplied laminates.