Materials chemistry

Composite materials

Use the roles of matrix, reinforcement and interface to explain composite properties, estimate directional stiffness and understand processing and failure modes.

1 Lower secondary 2 Upper secondary 3 Undergraduate 4 Advanced 5 Research

IntuitionCombine materials, combine advantages

Inspect fibres embedded in a continuous matrix and the interphase that transfers load; compare aligned and differently oriented reinforcement.

SchoolConstituents and simple estimates

Definition: Composite material

Example

Solution

Vm = 0.60, so EL ≈ 0.40(70) + 0.60(3) = 29.8 GPa. This is an ideal load-sharing estimate, not a guarantee for a real laminate.

Composite architecture and typical trade-offs
Architecture	Characteristic
Aligned continuous fibres	High axial properties; anisotropic
Woven fabric	Multiple directions; crimp can reduce axial stiffness
Particle-filled matrix	Can improve wear, stiffness or dimensional stability

UndergraduateLoad transfer and anisotropy

References

An Introduction to Composite Materials · D. Hull, T. W. Clyne, 1996