Effect of Pile Height on the Mechanical Properties of 3D Woven Spacer Composites

Three-dimensional (3D) woven spacer fabric is produced by connecting two woven fabric layers with the vertical pile yarns in the center part. Their composites have great potential for use in construction, automotive, marine, and aerospace applications due to outstanding mechanical properties. In this paper, 3D woven spacer fabrics with three thickness levels (4 mm, 10 mm and 20 mm) made of E-glass fibre, were used. Then 3D woven spacer fabrics were fabricated into their corresponding composites by hand lay-up technique using green epoxy resin. Characterization was done at both stages i.e. fabric and composite. Bending length and modulus of 3D woven spacer fabrics were decreased while the stiffness of the fabric was increased with increase in sample thickness. While in 3D woven spacer composites, 20 mm thick composite was more needle penetration resistant as compared to the 10 mm and 4 mm thick composites. Flexural and slow velocity impact performance of the 3D woven spacer composites was reduced with the increase of sample thickness. Flexural behaviour was better in weft direction as compared to the warp direction in all samples. Furthermore, 4 mm thick composite showed the highest value of energy absorbed and least deformation during the drop weight impact test.