This paper evaluates a loop bending test that can measure the intrinsic strength and breaking strain of carbon fibers. The discussion extends from the applicability of a closed-form solution for prismatic bar flexure, subjected to large deformations, to an interpretation of the test results. The assumptions embedded in the closed-form solution are verified by finite element computer simulations of the loop test.
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References
1.
BatheK. J., “Finite Element Procedures in Engineering Analysis,” Prentice-Hall, NY, 1982.
2.
BeetzCh P., A Self-consistent Weibull Analysis of Carbon Fiber Strength Distribution, Fiber Sci. Tech.16, 81 (1982).
3.
BeetzCh P., The Analysis of Carbon Fiber Strength Distributions Exhibiting Multiple Modes of Failure, Fiber Sci. Tech.16, 45 (1982).
4.
BoretosJ.EdenM., “Contemporary Biomaterials,” Noyes Publications, Park Ridge, NJ, 1984.
5.
ChaudharyH. B.BatheK. J., A Solution Method for Static and Dynamic Analysis of the Three-dimensional Contact Problems with Friction,”Comput. Struct.24, 855 (1985).
6.
FigueiredoJ. L., “Carbon Fibers, Filaments and Composites,” Kluwer Academic Publishers, Dorndrecht, The Netherlands, 1990.
7.
GogginP., “A Method of Measuring the Quality of Carbon Fibers,” AERE-R7790, Atomic Energy Research Establishment, Harwell, U.S.
8.
HitchonJ. W.PhilipsD. C., The Dependence of the Strength of Carbon Fibers on Length, Fiber Sci. Tech.12, 217 (1979).
9.
Japanese industrial standard methods for carbon fibers, JISR-7801, 1980.
10.
JohnsonJ. W., Factors Affecting the Tensile Strength of Carbon-graphite Fibers, Appl. Polymer Symp.9 (10), 229 (1969).
11.
KrucinskaI., Evaluation of the Intrinsic Mechanical Properties of Carbon Fibers, Composites Sci. Tech.41, 287 (1991).
12.
KrucinskaI.StypkaT., Direct Measurement of the Axial Poisson's Ratio of Single Carbon Fibers, Composite Sci. Tech.41, 1–12 (1991).
13.
KrucinskiS.DokainishM., Finite Element Analysis of the Bioprosthetic Heart Valve Motion Accounting for Pliability of Cuspal Support, Proc. Int. Conf. on Nonlinear Eng. Computations, Swansea, U.K., 1991, p. 747.
14.
MoretonR., The Effect of Gauge Length on the Tensile Strength of RAE Carbon Fibers, Fiber Sci. Tech.2, 273 (1969).
15.
ZurekW.KrucinskaI., An Attempt to Evaluate the Intrinsic Strength and Strain of Carbon Fibers, Btittle matrix composites 2, BrandtA. M.MarshallJ. H., Eds., Elsevier, NY, 1988.