Effect of layer thickness on the bending properties of highly strained composites

High-strain composite materials are widely used in the field of deployable space structures due to their ability to be encapsulated and unfolded using stored strain energy to significantly reduce the weight and complexity of space structures. In order to better meet the needs of deployable space structures, this paper designed a reasonable counterweighted balanced column bending test fixture to ensure the accuracy of the test results, and prepared high-strain composite laminates with single-layer thicknesses of 20μm, 60μm, and 100μm at different layup angles by molding, and conducted column bending tests, analyzing the effect of single-layer thickness at different layup angles on the bending performance of high-strain composite materials. The results show that when the designed counterweight balance column bending fixture is used, the deviation of the fixture rotation angle in the test and the calculated result of the simplified model is less than 3°, which ensures the accuracy of the test; when the ply angle is 0_n, the thinner the single layer thickness, the greater the bending stiffness of the test piece, and the bending stiffness of the test pieces with different single layer thicknesses increases by 36.37% and 44.78% respectively, and this increase decreases with the increase of the number of plies; when the ply angle is 0/90_ns, the influence of the single layer thickness on the bending stiffness is the same as 0_n, that is, the thinner the single layer thickness, the greater the bending stiffness of the test piece, while when the ply angle is 0/±45/90_ns, the influence of the single layer thickness on the bending stiffness is the opposite, that is, the thinner the single layer thickness, the smaller the bending stiffness of the test piece; with the richer ply angles, the curvature that the test piece can achieve is significantly improved.