Materials for engineering, 3rd Edition - (Malestrom)

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Materials for engineering
6.4.2 The tensile strength of fibre composites (σ c )
Aligned, continuous fibre composites
We will assume that the fibres and the matrix possess a similar Poisson ratio
and that they are well-bonded so that they deform together. The load on the
composite will be shared between the two components in proportion to
their cross-sectional areas. There are two possibilities to consider: depending
on whether the failure strain of the matrix is greater than or less than that of
the fibre.
If the failure strain of the matrix is less than the failure strain of the fibre
(Fig. 6.11), at low values of f f , the failure stress of the composite, σ * c ,
depends primarily on the failure strength of the matrix, σ * m . The matrix
σ f
*
σ’ f
Stress
Fibre
σ m
*
Resin
Strain ε m
*
ε f
*
6.11 Stress–strain curves of fibre and matrix, with failure strain of
matrix < that of fibre.