A shear-lag model has been developed for the prediction of stress recovery
in a broken fiber embedded in a ductile-matrix composite. The model builds
on the original shear-lag model of (Cox HL. Br J Appl Phys 1952;3:72-9) by
introducing plasticity constitutive behavior into the matrix. The matrix is
assumed to be an elastic/perfectly-plastic material that deforms according
to J(2) flow theory. The use of a flow rule to govern the matrix deformati
on in this model differs from previous attempts to represent plasticity in
the matrix. A non-linear partial differential equation is obtained from the
model. Numerical solutions to the equation are obtained and compared to si
mpler shear-lag models which assume sliding at the fiber/matrix interface c
ontrolled by a uniform shear stress. Axisymmetric finite-element calculatio
ns were done to assess the validity of the shear-lag model. It proves to be
in good agreement with the finite-element analysis. Predictions of the she
ar-lag calculations suggest that the global load-sharing (GLS) strength mod
el of (Curtin WA. J Am Ceram Soc 1991;74:2837-45) is valid for a composite
with a yielding matrix that is elastically rigid. (C) 1999 Elsevier Science
Ltd. All rights reserved.