DID YOU KNOW? DTIC has over 3.5 million final reports on DoD funded research, development, test, and evaluation activities available to our registered users. Click
HERE to register or log in.
Accession Number:
ADA295187
Title:
A Computational Model for Progressive Damage and Failure of Fiber-Reinforced Ceramic Composites.
Descriptive Note:
Final rept. 12 Jul 94-12 Jan 95,
Corporate Author:
MATERIALS AND SYSTEMS RESEARCH INC SALT LAKE CITY UT
Report Date:
1995-02-01
Pagination or Media Count:
56.0
Abstract:
A computational model was developed to simulate the progressive damage of fiber-reinforced brittle matrix composites under uniaxial tensile loading. In conjunction with the basic material properties, this model used a size-distribution of the fiber-free zones as an input for the development of small penny-shaped cracks at the early stage of loading. Stable extension of such non-steady-state cracks and the transition from non-steady-state to steady-state cracks were modeled using a stress-intensity formulation for a partially-bridged penny-shaped crack. Stress-strain relation was simulated by calculating the total engineering strain in the gage section as a function of the applied stress. Strain energies of the non-steady-state cracks and displacements of the fibers in the sliding zones of the steady-state cracks were calculated to estimate the total strain. Two unidirectional fiber-reinforced composites were investigated to test the predictive capability of this model. The stress-strain relation predicted by the model was in good agreement with that measured experimentally for a SiC-reinforced calcium aluminosilicate composite. A SiC-reinforced magnesium aluminosilicate composite showed less cumulative strain before fracture due to premature fiber failure. MM
Distribution Statement:
APPROVED FOR PUBLIC RELEASE
