Bond Parameters to Improve Tensile Load Bearing Capacities of Co-Cured Single and Double Lap Joints with Steel and Carbon Fiber-epoxy Composite Adherends

Abstract

A co-cured joining method has several advantages over an adhesivelybonded joining method for its simple manufacturing process. It requires neither an adhesive nor surface treatment of the composite adherend and uses excess resin to bond both adherends, including composite adherend.

In this paper, the effects of bond parameters, including surface roughness on the steel adherend, stacking sequence of the composite adherend, and manufacturing pressure in the autoclave during the bonding process, on tensile load bearing capacities of plate-type co-cured single and double lap joints were investigated experimentally. Bond parameterswere related to interfacial parameterssuch asa contact area and adhesive thickness, which affected the joint strength. Experimental results were explained with respect to all of interfacial parameters and bond parameters through investigating failure surfaces of the steel adherend and a lot of data of tensile load bearing capacities. In order to predict tensile load bearing capacities of co-cured single and double lap joints, we considered two different failure models using stress distributions in both co-cured lap joints obtained from finite element analysis. Finally, optimal conditions to improve the joint strength of co-cured single and double lap joints have been presented.

Keywords

co-cured lap joint tensile load bearing capacity surface roughness stacking sequence manufacturing pressure

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References

1. Shin, K. C. and Lee, J. J. (2000). Tensile Load Bearing Capacity of Co-Cured Double Lap Joints, Journal of Adhesion Science and Technology, 14: 1539–1556.

2. Jones, R. , Chiu, W. K. and Paul, J. (1993). Designing for Damage Tolerant Bonded Joints, Composite Structures, 25: 201–207.

3. He, S. and Rao, M. D. (1994). Residual Stresses and Delamination Problems Induced by Co-Curing of Damped Composite Laminates, Journal of Composite Materials, 28: 112–129.

4. Kim, H. S. , Lee, S. J. and Lee, D. G. (1995). Development of a Strength Model for the Co-Cured Stepped Lap Joints Under Tensile Loading, Composite Structures, 32: 593–600.

5. Scott, M. L. , Raju, J. A. S. and Cheung, A. K. H. (1998). Design and Manufacturing of a Post-Buckling Co-Cured Composite Aileron, Composite Science and Technology, 58: 199–210.

6. Olivier, P. and Cottu, J. P. (1998). Optimisation of the Co-Curing of Two Different Composites with the Aim of Minimising Residual Curing Stress Levels, Composite Science and Technology, 58: 645–651.

7. Choi, J. H. and Lee, D. G. (1997). Torque Capacity of Co-Cured Tubular Lap Joints, Journal of Composite Materials, 31: 1381–1396.

8. Lee, S. W. , Lee, D. G. and Jeong, K. S. (1997). Static and Dynamic Torque Characteristics of Composite Co-Cured Single Lap Joint, Journal of Composite Materials, 31: 2188–2201.

9. Cho, D. H. , Lee, D. G. and Choi, J. H. (1997). Manufacture of One-Piece Automotive Drive Shafts with Aluminum and Composite Materials, Composite Structures, 38: 309–319.

10.

10. Cho, D. H. and Lee, D. G. (1998). Manufacturing of Co-Cured Composite Aluminum Shafts with Compression During Co-Curing Operation to Reduce Residual Thermal Stresses, Journal of Composite Materials, 32: 1221–1241.

11.

11. Lee, D. G. and Cho, D. H. (2000). Prediction of the Tensile Load Capability of Co-Cured Steel-Composite Tubular Single Lap Joints Considering Thermal Degradation, Journal of Composite Materials, 34: 689–722.

12.

12. Cho, D. H. and Lee, D. G. (2000). Optimum Design of Co-Cured Steel-Composite Tubular Single Lap Joints Under Axial Load, Journal of Adhesion Science and Technology, 14: 939–963.

13.

13. Shin, K. C. , Lee, J. J. and Lee, D. G. (2000). A Study on the Lap Shear Strength of a Co-Cured Single Lap Joint, Journal of Adhesion Science and Technology, 14: 123–139.

14.

14. Shin, K. C. and Lee, J. J. (2000). Prediction of the Tensile Load Bearing Capacity of a Co-Cured Single Lap Joint Considering Residual Thermal Stresses, Journal of Adhesion Science and Technology, 14: 1691–1704.

15.

15. Wilkins, D. J. et al. (1994). Japanese Research and Development in the Manufacturing of Polymer Composite Structures, National Technical Information Service (NTIS) Report #PB94-161403.

16.

16. O’Brien, T. K. (1995). Test Methods for Characterizing Composite Skin-Stringer Debonding, NASA Langley Research Center, Hampton, VA.

17.

17. Crane, L. W. , Hamermesh, C. L. and Maus, L. (1976). Surface Treatment of Cured Epoxy Graphite Composite to Improve Adhesive Bonding, SAMPE Journal, 12: 6–9.

18.

18. Parker, B. M. and Waghorne, R. M. (1982). Surface Pretreatment of Carbon Fiber-Reinforced Composites for Adhesive Bonding, Composites, 13: 280–288.

19.

19. Lee, D. G. , Kim, K. S. and Im, Y. T. (1991). An Experimental Study of Fatigue Strength for Adhesively Bonded Tubular Single Lap Joints, Journal of Adhesion, 35: 39–53.

20.

20. Renton, J. W. and Vinson, J. R. (1975). On the Behavior of Bonded Joints in Composite Material Structures, Engineering Fracture Mechanics, 7: 41–60.

21.

21. Goeij De, W. C. , van Tooren, M. J. L. and Beukers, A. (1999). Composite Adhesive Joints under Cyclic Loading, Materials and Design, 20: 213–221.

22.

22. Oh, J. H. , Kim, J. K. , Lee, D. G. and Jeong, K. S. (1999). Interlaminar Shear Behavior of Thick Carbon/Epoxy Composite Materials, Journal of Composite Materials, 33: 2080–2115.

23.

23. (1995). Annual Book of ASTM Standards (General Products,Chemical Specialties,and End Use of Products), Vol. 15, American Society for Testing and Materials, Philadelphia, PA.

24.

24. (1998). ABAQUS/Standard User’s Manual, Hibbitt, Karlsson & Sorensen, Pawtucket, RI.

25.

25. Reddy, H. N. (1997). Mechanics of Laminated Composite Plates: Theory and Analysis, pp. 752–754, CRC Press, Inc., Boca Raton, Florida.

26.

26. Ye, L. (1988). Role of Matrix Resin in Delamination Onset and Growth in Composite Laminates, Composites Science and Technology, 33: 257–277.