Analyses Of Residual Strength Of 2.5D Woven Composites After Impact

Based on the RVE method, this article takes twill laminates in comparison and investigates the tensile strength of pre-and-post-impact of 2.5D woven composite and the laminate separately by means of theory and experiment.Based on the theory of 3D cumulative damage, the models of the two materials under impact have been set up in ANSYS and the author calculates the whole process of impact and calculates the damage of the two materials under the impact load with different energy. The author calculates the residual strength of the two materials by means of Softening inclusion and Cumulative damage.The author produces the test pieces of tensile and compression of the two kinds material and carry on the experiment. The experiments of low-velocity impact and residual tensile strength of the two materials are carried on. And then the test pieces after impact are amended into standard tensile pieces and tested in tensile. In the end, the article gets the residual strength of the two materials with the same energy.The result of FEM is compared with the one got from experiment. The comparison proves that it is reasonable to select the methods and 2.5D woven composites have good property of impact resistance. The comparisons between the two calculation methods of residual strength and the experiments suggest that the Cumulative damage method can be more scientific and more effective in the prediction of residual strength of 2.5D woven composites and other materials than the Softening inclusions method. At last, the ratios of strength degradation between the pre-impact and impacted have been compared by experiment. It is clearly shown that 2.5D woven composites can resist more energy of impact than laminates and the yards in Z-direction can improve the property of interlayer effectively.