Effects of hygrothermal environmental conditions on compressive strength of CFRP stitched laminates

Experimental and analytical investigation was conducted to understand the hygrothermal properties of uniweave T300/QY9512 laminates. Tests were performed under hygrothermal and room temperature environment separately. Effect of stitching parameters upon strength performance of laminates was predicted using FEM model. Compressive strength of laminates, under different environmental conditions, was also predicted. Test results have shown that hygrothermal environment condition has a severe effect on the compressive strength of laminates and the reduction in compression strength for stitched laminates reached up to 50%. Stitching might improve the compressive strength of laminates depending upon the environmental conditions and lay-up sequence of stitched laminates.