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Crack diffusion coefficient - A candidate fracture toughness parameter for short fiber compositesIn brittle matrix composites, crack propagation occurs along random trajectories reflecting the heterogeneous nature of the strength field. Considering the crack trajectory as a diffusive process, the 'crack diffusion coefficient' is introduced. From fatigue crack propagation experiments on a set of identical SEN polyester composite specimens, the variance of the crack tip position along the loading axis is found to be a linear function of the effective 'time'. The latter is taken as the effective crack length. The coefficient of proportionality between variance of the crack trajectory and the effective crack length defines the crack diffusion coefficient D which is found in the present study to be 0.165 mm. This parameter reflects the ability of the composite to deviate the crack from the energetically most efficient path and thus links fracture toughness to the microstructure.
Document ID
19880049718
Document Type
Conference Paper
Authors
Mull, M. A. (Case Western Reserve Univ. Cleveland, OH, United States)
Chudnovsky, A. (Case Western Reserve Univ. Cleveland, OH, United States)
Moet, A. (Case Western Reserve University Cleveland, OH, United States)
Date Acquired
August 13, 2013
Publication Date
January 1, 1987
Subject Category
COMPOSITE MATERIALS
Meeting Information
nternational Conference on Composite Materials(London)
Funding Number(s)
CONTRACT_GRANT: NAG3-585-2
Distribution Limits
Public
Copyright
Other