In this paper the effects of temperature and humidity on the stress field of laminated composites are investigated. A three-dimensional finite element program based on dis placement field was developed and the stress field induced by hygrothermal and/or initial strain was evaluated. Boundary conditions of zero-stress on the free surfaces were not taken into account in this preliminary investigation.
Numerical results of the three-dimensional stress field for [90/0]2s laminates were plotted as a function of position. It is observed that some of the stress components induced by hygrothermal change are significant to cause failure of the laminate.
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References
1.
Fried, N. "Degradation of Composite Materials: The Effects of Water on Glass-Reinforced Plastics," in Mechanics of Composites, Proceedings of the 5th Symposium on Naval Structural Mechanics. Philadelphia, PA:Pergamon Press, pp. 813-837 (1967).
2.
Shen, C.-H. and G.S. Springer. "Moisture Absorption and Desorption of Composite Materials ," Journal of Composite Materials, 10:2-20 (January, 1976).
3.
Whitney, J.M. "Moisture Diffusion in Fiber Reinforced Composites," Proceedings of the 1978 International Conference on Composite Materials, Toronto, Canada, pp. 1584-1601 (1978 ).
4.
DeIasi, R. and J.B. Whiteside. "Effects of Moisture on Epoxy Resins and Composites," ASTM-STP658, pp. 2-20 (1978).
5.
Shirrel, C.D. "Diffusion of Water Vapor in Graphite/Epoxy Composites," ASTM-STP658, pp. 21-42 (1978).
6.
Whitney, J.M. and C.E. Browning. "Some Anomalies Associated with Moisture Diffusion in Epoxy Matrix Composite Materials," ASTM-STP658, pp. 43-60 (1978).
7.
Blikstad, M. , P.O.W. Sjoblom and T.R. Johannesson. "Long-Term Moisture Absorption in Graphite/Epoxy Angle Ply Laminates," Journal of Composite Materials, 18:32-46 (January, 1984).
Springer, G.S. "Environmental Effects on Epoxy Matrix Composites ," ASTM-STP674, pp. 291-312 (1979).
10.
Shen, C.-H. and G.S. Springer. "Environmental Effects on the Elastic Moduli of Composite Materials; 'Journal of Composite Materials , 11:250-264 (July, 1977).
11.
Shen, C.-H. and G.S. Springer. "Effects of Moisture and Temperature on the Tensile Strength of Composite Materials," Journal of Composite Materials, 11:2-16 (January, 1977).
12.
Lee, B.L., R.W. Lewis and R.E. Sacher. "Environmental Effects on the Mechanical Properties of Glassfiber/Epoxy Resin," Proceedings of the 1978 International Conference on Composite Materials, Toronto , Canada, pp. 1560-1583 (1978).
13.
Phillips, D.C. , J.M. Scott and N. Buckley. "The Effects of Moisture on the Shear Fatigue of Fiber Composites," Proceedings of the 1978 International Conference on Composite Materials, Toronto, Canada, pp. 1544-1559 (1978).
14.
Watanabe, M. "Effects of Water Environment on Fatigue Behavior of Fiberglass Reinforced Plastics," ASTM-STP674, pp. 345-367 (1979).
15.
Chamis, C.C. and J.H. Sinclair. "Durability/Life of Fiber Composites in Hygrothermal Environments ," ASTM-STP 787, pp. 298-367 (1982).
16.
Browning, C.E. "The Mechanisms of Elevated Temperature Property Losses in High Performance Structural Epoxy Resin Matrix Materials after Exposure to High Humidity Environments," Proceedings of the 1978 International Conference on Composite Materials, Toronto, Canada, pp. 1527-1543 (1978).
17.
Crossman, F.W. , R.E. Mauri and W.J. Warren. "Moisture Altered Viscoelastic Response of Graphite/Epoxy Composites," ASTM-STP658, pp. 105-220 (1978).
18.
Flaggs, D.L. and F.W. Crossman. "Analysis of the Viscoelastic Response of Composite Laminates During Hygrothermal Exposure," Journal of Composite Materials , 15:21-39 (January, 1981).
19.
Hahn, H.T. and R.Y. Kim. "Swelling of Composite Laminates," ASTM-STP658, pp. 98-120 (1978).
20.
Maymon, G., R.P. Briley and L.W. Rehfield. "Influence of Moisture Absorption and Elevated Temperature on the Dynamic Behavior of Resin Matrix Composites: Preliminary Results," ASTM-STP658, pp. 221-233 (1978).
21.
Carter, H.G. , K.G. Kiber and J.D. Reynolds. "Fundamental and Operational Glass Temperature of Composite Resins and Adhesives," ASTM-STP658, pp. 84-97 (1978).
22.
Hahn, H.T. "Hygrothermal Damage in Graphite/Epoxy Laminates," presented at the ASME, Winter Annual Meeting, Miami Beach, Florida, November 16.21, 1985.
23.
Whitney, J.M., I.M. Daniel and R.B. Pipes.Experimental Mechanics of Fiber Reinforced Composites Materials . Prentice-Hall (1982).
24.
Tsai, S.W. and H.T. Hahn.Introduction to Composite Materials. Lancaster, PA:Technomic Publishing Co. (1980).
25.
Lo, S.Y. and H.T. Hahn. "Swelling of Kevlar49/Epoxy and S2-Glass/Epoxy Composites ," Proceedings of the 4th International Conference on Composite Materials. T. Hayashi , ed. Tokyo (1982).
26.
Bouadi, H. "Hygrothermal Effects on Complex Moduli of Composite Laminates," Ph.D. Dissertation, Department of Engineering Sciences, University of Florida (December, 1987).
