Compression behavior of ultra-high modulus carbon/epoxy composites using ASTM D6641 and SACMA SRM 1R-94

The compression modulus and compression strength of a proprietary ultra-high modulus carbon/epoxy composite are experimentally determined using SACMA SRM 1R-94 and ASTM D6641 for laminates with stacking sequences of [(0/ ± 60) s ] 2 and [(+60/0/−60) s ] 2 . The moduli of both laminates are experimentally shown to be statistically equivalent; the strength of the [(0/ ± 60) s ] 2 laminate is shown to be significantly less than the [(+60/0/−60) s ] 2 laminate. A finite element model is developed for each compression test to predict the compression modulus and compression strength using the built-in damage progression algorithm in Abaqus. Premature end crushing is predicted in the modulus specimen of SACMA SRM 1R-94 for the [(+60/0/60) s ] 2 laminate. End crushing in the modeled SACMA SRM 1R-94 strength specimen is predicted to occur immediately after ultimate laminate failure for the [(+60/0/60) s ] 2 laminate. Fiber misalignment is found to significantly affect the predicted compression modulus and compression strength of the ultra-high modulus carbon/epoxy composite analyzed.