Page 390 - Engineered Interfaces in Fiber Reinforced Composites

SYMBOLS AND ABBREVIATIONS

a crack length or fiber radius (= half of fiber diameter, 42)
Aa incremental crack length
b matrix outermost radius
h breadth or width
C compliance
C* measured compliance when residual displacements are present
size of damage zone
CO
d diameter
4 stitch thread diameter
E elastic modulus (Ec fiber; E, matrix; E, composite)
Young’s modulus in the first in-plane principal direction (= EL,
El I
longitudinal Young’s modulus)
E22 Young’s modulus in the second in-plane principal direction (= ET,
transverse Young’s modulus)
E effective Young’s modulus
E energy (Ek kinetic energy; EB electron beam energy)
G potential energy release rate (with units of kJ/m2)
critical potential energy release rate
GC
Ge strain energy release rate in edge notched tension test
GI mode 1 interlaminar fracture toughness (Gl-ll: mixed mode I & 11)
GTC composite interlaminar fracture toughness
Gf;, neat resin fracture toughness
GlIc mode I1 interlaminar fracture toughness
GK total potential energy release rate
G elastic component of total potential energy release rate
Gic interfacial fracture toughness
C shear modulus
GLT in-plane shear modulus of laminate
G, shear modulus of matrix
h (or t) height (or thickness)
hv total absorbed X-ray photon energy
I moment of inertia
composite J integral
Jc
K stress intensity factor (with units of MPa dm)
Kc stress intensity factor of composite
Kttl stress intensity factor of matrix material
KK crack growth resistance
L half span

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