The effect of debonding on various moduli of short fiber composites wa
s studied by developing an analytical model. It was assumed that debon
ding of the fiber-matrix interface initiated at the end of the fibers
and progressed to the center. Debonding along only a few percent of th
e fiber length substantially reduced the moduli of the composite, espe
cially for relatively high-volume fractions of reinforcement. Results
were compared to an existing model, in which debonding was assumed to
occur in a sector around the fiber and all along the length of the fib
er. It was found that debonding along the length of the fiber reduced
the modulus of the composite significantly more than debonding around
a sector, for the same percentage of the fiber debonded. It was not ju
st the percentage of the fiber debonded which effected the moduli, but
also the manner in which the debonding occurred. Copyright (C) 1996 E
lsevier Science Ltd.