Masahiko Kimbara

Shear Property of 3D Braided Composite.

Shear property of 3D braided composites with various thickness and fiber-angle, which were fabricated using carbon fiber and epoxy resin was measured using V-notch beam specimens (modified Iosipescu method). The shear strength and modulus (τZX, GZX respectively) in the plane containing braid axis (Z) were fairly higher than those of the in-plane shear properties of traditional unidirectional (UD) laminates and increased with the braiding angle up to 45°. On the other hand shear property in the plane perpendicular to the braid axis (τXY and GXY) was shown to be as low as out-of-plane property of the UD laminates. Anisotropic shear property of the specimen depending on the load direction was observed. Strength and modulus determined under the load vertical to the braid direction, (GZXL, σZXL respectively) were higher than those in the case of horizontal (GZXT, σZXT respectively). Especially the shear strength differed by a factor of 3.