Characterization and modeling of three-dimensional woven composites

The objectives of this research are: (1) to fully develop the chemical blowing method. (2) Characterize 3D woven cellular matrix composites for different fibers and structures. (3) Develop an FEA model simulating elastic properties.; A chemical foaming method was developed to empty resin pockets in 3D woven carbon and glass composites to achieve lower density. Density reduction of glass dellular matrix composites (CMC) C1 was 11.57–14.51%, while that of Prepreg CMC P was 6.01. Carbon CMC C1 achieved a density reduction of 25.40–24.03%.; For Glass composites, Glass CMC weft direction specimens showed significant improvements at 29.31–30.26% in specific Young's modulus. CMC resisted the largest number of strikes, and it also dissipated more cumulative energy than the other two systems.; For Carbon composites, all the specimens failed under a brittle failure mode in tensile test. Specific Young's modulus of CMC in weft direction improved 9.8%–19% while that of warp direction improved 22.8–24.9%. Specific compression modulus of CMC in weft direction was 13–25% stiffer than regular matrix composites (RMC) while that of warp direction is 9–20%. Specific tangent moduli of CMC were similar to that of the RMC.; An FEA model was developed using the smallest repeating unit cell in 3D orthogonal woven structure. Good agreement between the FEA model and the experiments were found in CMC.; Chemical blowing method was proven to be an effective alternate to physical blowing method. Excess amount of sodium bicarbonate may harm the tensile properties of the composites.