An experimental study was performed to determine the effect of type of tabbing material and tab taper on the measured axial compressive strength of a unidirectional carbon/epoxy material. Two types of tabbing materials (hot-rolled, low carbon steel and glass-fabric/epoxy) and two tab taper geometries (untapered and 30° taper) were utilized. Additionally, the influence of partial tab debonding on the measured compressive strength was determined. A standard IITRI compression test fixture was used. Tapered steel tabs provided consistently higher compressive strengths than tapered glass-fabric/epoxy tabs, or untapered steel or glass-fabric/epoxy tabs. Deliberately introducing regions of tab debonding in untapered glass-fabric/epoxy tabbed specimens resulted in only a small decrease in compressive strength.
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References
1.
1. 1989. “Hercules AS4/3501–6 Carbon/Epoxy Prepreg Material,”Magna, Utah: Hercules, Inc.
2.
2. 1988. “Mechanical Properties of Hercules AS4/3501–6 Carbon/Epoxy Unidirectional Composite Materials,”Magna, Utah: Hercules, Inc.
3.
3. Hofer, K. E., Jr. and P. N. Rao. 1977. “A New Static Compression Fixture for Advanced Composite Materials.”Journal of Testing and Evaluation, 5(4):278–283.
4.
4. 1975 (first issue date). “Compressive Properties of Unidirectional or Crossply Fiber-Resin Composites,” ASTM Standard D 3410–87. Philadelphia, Pennsylvania: American Society for Testing and Materials.
5.
5. Westberg, R. L., and M. G. Abdallah. 1987. “An Experimental and Analytical Evaluation of Three Compressive Test Methods for Unidirectional Graphite/Epoxy Composites,” Report RI-86B12100, Magna, Utah: Hercules, Inc.
6.
6. Adsit, N. R.1983. “Compression Testing of Graphite/Epoxy,” in Compression Testing of Homogeneous Materials and Composites, ASTM STP 808, R. Chait and R. Puperno, eds., Philadelphia, Pennsylvania: American Society for Testing and Materials, pp. 175–186.
7.
7. Lamothe, R. M., and J. Nunes. 1983. “Evaluation of Fixturing for Compression Testing of Metal Matrix and Polymer Matrix Composites,” in Compression Testing of Homogeneous Materials and Composites, ASTM STP 808, R. Chait and R. Paperno, eds., Philadelphia, Pennsylvania: American Society for Testing and Materials, pp. 241–253.
8.
8. Chamis, C. C., and J. H. Sinclair. 1985. “Longitudinal Compression Failure Modes in Fiber Composites: End Attachment Effects in IITRI Type Test Specimens,”Journal of Composites Technology and Research, 7(4):129–135.
9.
9. Sinclair, J. H., and C. C. Chamis. 1983. “Compressive Behavior of Unidirectional Fibrous Composites,” in Compressive Testing of Homogeneous Materials and Composites, ASTM STP 808, R. Chait and R. Paperno, eds., Philadelphia, Pennsylvania: American Society for Testing and Materials, pp. 155–174.
10.
10. Clark, R. K., and W. B. Lisagur. 1981. “Compression Testing of Graphite/Epoxy Composite Materials,” in Test Methods and Design Allowables for Fibrous Composites. ASTM STP 734, C. C. Chamis, ed., Philadelphia, Pennsylvania: American Society for Testing and Materials, pp. 34–53.
11.
11. Berg, J. S., and D. F. Adams. 1989. “An Evaluation of Composite Material Compression Test Methods,”Journal of Composites Technology and Research, 11(2):41–46.
12.
12. Cunningham, M. E., S. V. Schoultz and J. M. Toth, Jr.. 1985. “Effect of End Tab Design on Tension Specimen Stress Concentration,” in Recent Advances in Composites in the United States and Japan, ASTM STP 864, J. R. Vinson and M. Taya, eds., Philadelphia, Pennsylvania: American Society for Testing and Materials, pp. 253–262.
13.
13. 1986 (reapproved 1982). “Fiber Content of Resin-Matrix Composites by Matrix Digestion,” in ASTM Standard D 3171–76, Vol. 15.03, Philadelphia, Pennsylvania: American Society for Testing and Materials.
14.
14. 1986 (reapproved 1980). “Void Content of Reinforced Plastics,” in ASTM Standard D 2734–70, Vol. 15.03, Philadelphia, Pennsylvania: American Society for Testing and Materials.
15.
15. 1989. “Techkits A-12 Epoxy Adhesive,”Demurest. New Jersey: Techkits, Inc.
16.
16. Odom, E. M., and D. F. Adams. 1990. “Failure Modes of Unidirectional Carbon/Epoxy Composite Compression Specimens”Composites, 21(4):289–296.
17.
17. Popov, E. P.1976. Mechanics of Materials, Second Edition.Englewood Cliffs, New Jersey: Prentice-Hall, Inc., pp. 461–500.
18.
18. Smoot, M. A.1982. “Compressive Response of Hercules AS1/3501–6 Graphite/Epoxy Composites,” Report CCM-82–16. Newark, Delaware: Center for Composite Materials, University of Delaware.
