Experiments and micromechanical models for creep-rupture in polymer matrix composites. Progress report, June 15, 1984-June 14, 1985
Technical Report
·
OSTI ID:6052407
Time dependent failure in the long term (stress- or creep-rupture) results from thermally or environmentally activated growth of flaws in the fibers, or viscoelastic creep in the matrix, or a combination of both. This creep causes a widening pattern of stress redistribution on fibers near fiber breaks that is ultimately felt as increasing overload factors in time. As a result of these two mechanisms, sequences of adjacent fiber breaks grow in time, one of which eventually becomes unstable and fractures the composite. Purpose in this research is to develop statistical and micromechanical models of this failure process which can be used to forecast the long-term reliability of large composite structures. Components of these models are constitutive laws for creep of the matrix in shear, statistical distributions for flaws in the fibers and their kinetics of breakdown, and a modified shear-lag analysis for determining the stress redistribution on fibers adjacent to breaks; the focus is on power law versions of the various models in both stress and time, since these yield the most tractable analysis and useful results. Goal is to obtain short-term strength and long-term lifetime distributions and to determine the dependence of scale and shape parameters on stress level, fiber variability shape parameters, matrix creep exponents and exponents for stochastic breakdown of fibers under stress.
- Research Organization:
- Cornell Univ., Ithaca, NY (USA). Sibley School of Mechanical and Aerospace Engineering
- DOE Contract Number:
- FG02-84ER45112
- OSTI ID:
- 6052407
- Report Number(s):
- DOE/ER/45112-1; ON: DE85009533
- Country of Publication:
- United States
- Language:
- English
Similar Records
Probabilistic models of the stress-rupture of composite materials: Phase V. Progress report, June 15, 1981-June 14, 1982
Probabilistic models of the stress-rupture of composite materials: Phase IV. Progress report, June 15, 1980-June 14, 1981
Experiments and micromechanical models for creep-rupture in polymer matrix composites: Progress report for period June 15, 1984-June 14, 1987
Technical Report
·
Thu Dec 31 23:00:00 EST 1981
·
OSTI ID:5434925
Probabilistic models of the stress-rupture of composite materials: Phase IV. Progress report, June 15, 1980-June 14, 1981
Technical Report
·
Sat Feb 28 23:00:00 EST 1981
·
OSTI ID:6509046
Experiments and micromechanical models for creep-rupture in polymer matrix composites: Progress report for period June 15, 1984-June 14, 1987
Technical Report
·
Sun Nov 30 23:00:00 EST 1986
·
OSTI ID:7007782