Page 182 - 3D Fibre Reinforced Polymer Composites

Stitched Composites 17 1
post-impact mechanical properties can be improved with large amounts of stitching (see
Section 8.5). Therefore, it appears that composites can be heavily stitched to provide
maximum impact damage tolerance without reducing the in-plane mechanical properties
any more than would occur with low density stitching.

700 7
GlassIPolyester
650:
2 600:
v)
3
5 550-
- 500:
.-
v)
I-" 450-
-
400
- Kevlar/PVB-P henol
350
I

-
70 GladPolyester

N- 65-
E
2 60-
E
5 55-
0,
C
22 50-
tj
a,
5 45- e---------
c Kevlar/PVB-Phenol
40-
-
35
I

Figure 8.5 The effect of stitch density on the (a) Young's modulus and (b) tensile
strength of a glass/polyester and KevlarPVB-phenol composite that were stitched under
identical conditions. Data from Kang and Lee (1994).