Coupled Deformation Properties of Anti-Symmetrical Laminate Composites

Anti-symmetrical laminate composites exhibit a coupling effect between tensile stress and twisting deformation, and are very attractive as blade materials for aircraft engines. Blades made of anti-symmetrical laminate composites can automatically adjust their stagger angle to a better aerodynamic configuration with changing rotational speed. Thus, the aerodynamic efficiency and stability of aircraft engines can be greatly improved. In this study, the coupled deformation properties of anti-symmetrical laminate composites were evaluated with tensile tests. Two kinds of specimens fabricated from carbon/epoxy laminate composites with different anti-symmetrical stacking sequences were tested. On the basis of the tensile-test results, the anti-symmetrical laminate composites were then used as blade materials. The coupled deformation of the test blades at high rotational speed was evaluated by spin tests and FEM analyses. It was demonstrated that test blades twisted about 4° at 10000rpm.