A study was undertaken to investigate the loading rate effect on delamination fracture in itiation toughness of a thermoplastic composite. For this purpose, double cantilever beam specimens of graphite/PEEK were tested in a displacement controlled mode using an Instron tensile machine. Specimens were loaded at various crosshead speeds ranging from 0.05 cm/min to 100 cm/min. The interlaminar fracture toughness was found to decrease with increasing loading rate, and this decrease was up to 65 percent over the five decades of loading rate employed.
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References
1.
Miller, A.G. , P.E. Hertzberg and V.W. Rantala "Toughness Testing of Composite Materials," SAMPE Quarterly, pp. 36-42 (January 1981).
2.
Hunston, D.L. and W.D. Bascom "Effects of Layup, Temperature, and Loading Rate in Double Cantilever Beam Tests of Interlaminar Crack Growth ," Composites Technology Review, 5(4).118-119 (Winter 1983).
3.
Aliyu, A.A. and I.M. Daniel. "Effects of Strain Rate on Delamination Fracture Toughness of Graphite/Epoxy," Delamination and Debonding of Materials, ASTM STP 876, W S. Johnson, ed. American Society for Testing and Materials, Philadelphia , pp. 336-348 (1985).
4.
Damel, I.M., I. Shareef and A.A. Aliyu. "Rate Effects of Delamination Fracture Toughness of a Toughened Graphite/Epoxy," to be published in ASTM STP of Symposium on Toughened Composites, Houston , (March 13-15, 1985).
5.
Smiley, A.J. "Rate Sensitivity of Interlaminar Fracture Toughness in Composite Materials ," M. S. Thesis, Center for Composite Materials, University of Delaware, Newark, Delaware (December 1985)
6.
Devitt, D.F. , R.A. Schapery and W.L. Bradley "A Method for Determining Mode I Delamination Fracture Toughness of Elastic and Viscoelastic Composite Materials," Journal of Composite Materials, 14:270-285 (1980).
7.
Wilkins, D.J. , J.R. Eisemann, R.A. Camin, W.S. Margolis and R.A. Benson. "Characterizing Delamination Growth in Graphite-Epoxy ," Damage in Composite Materials: Basic Mechanisms, Accumulation, Tolerance, Characterazation, ASTM STP 775, K. Reifsnider , ed. American Society for Testing and Materials, Philadelphia, pp. 168-183 (1982).
8.
Mall, S. and W.S. Johnson. "Characterization of Mode I and Mixed-Mode Failure of Adhesive Bonds Between Composite Adherends," Composite Materials. Testing and Design (Seventh Conference), ASTM STP 893, J. M. Whitney, ed. American Society for Testing and Materials, Philadelphia, pp. 322-334 (1986).
