Heating Cycle Design for Thick Composite Laminates Using Curing Processes for Thin Laminates

Abstract

A new method has been developed to determine the curing cycles for thick laminates. The method uses numerical simulation together with knowledge of the conventional curing process for thin laminates. Once the process control parameters have been introduced, an iterative procedure is employed to arrive at the optimal heating cycles for thick laminates. Autoclave curing processes have been carried out using conventional cycles for (1 mm) laminates, as well as optimised cycles for thick section (12.5 mm) laminates. The interlaminar shear strengths of thick laminates, processed using the two types of curing cycles have been determined. Results show that there is no difference in the interlaminar shear strengths of laminates produced using the optimised and conventional curing cycles, but the curing times can be greatly reduced for the optimised curing cycle.

Keywords

optimal curing cycle heating cycle controlling parameters thick composite laminates temperature degree of cure

Get full access to this article

View all access options for this article.

References

1. Saliba, T.E. , Quinter S.R. and Abrams, F.L. (1991). Expert model process control of composite materials in a press. In: How Concept Becomes Reality. Proceedings of the 36 International SAMPE Symposium. San Diego, CA, pp. 1487-1497.

2. Servais, R.A. , Lee, C.W. and Browning, C.E. (1986). Intelligent processing of composite materials. SAMPE J., 22: 14-18.

3. Loos, A.C. and Springer, G.S. (1983). Curing of epoxy matrix composites. Journal of Composite Materials, 17(3): 135-169.

4. Kardos, J.L. , Dudukovic, M.P. and Dave, R. (1986). Void growth and resin transport during processing of thermosetting-matrix composites. In: Advances in Polymer Science-Vol. 80, Epoxy Resins and Composites. Vol. IV. Springer Verlag, Berlin, FRG, pp. 101-124.

5. Mallow, A.R. , Muncaster, F.R. and Campbell, F.C. (1986). Science based cure model for composites. In: Proceedings of the American Society for Composites-First Technical Conference. Dayton, OH, pp. 171-186.

6. Hanks, D.E. , Lee, M.C. , Young, C.R. and Tajima, Y.A. (1988). Processing science of thick-section composites. SAMPE Q, 19(2): 19-28.

7. LeClair, S.R. and Abrams, F.L. (1988). Qualitative process automation. Int. J. Integ. Manuf., 2(4): 205-211.

8. Lee, C W. (1986). Composites cure process control by expert systems. In: Proceedings of the American Society for Composites-First Technical Conference. Dayton, OH, pp. 187-196.

9. Ciriscioli, P.R. and Springer, G.S. (1991). An expert system for autoclave curing of composites. J. Compos. Mat., 25: 1542-1587.

10.

10. Pillai, Vikram , Beris, Antony N. and Dhurjati, Prasad (1997). Intelligent curing of thick composites using a knowledge-based system. Journal of Composite Materials, 31(1): 22-51.

11.

11. Martinez, G.M. (1991). Fast cures for thick laminated organic matrix composites. Chem. Eng. Sci., 46(2): 439-450.

12.

12. Nagendra, S. and Loos, A.C. (1989). Optimization of curing process of filament wound composite. In: Tomorrow Materials: Today. Proceedings of the 34th International SAMPE Symposium. Reno, NV, pp. 1853-1867.

13.

13. Bogetti, T.A. and Gillespie, J.W. (1991). Two dimensional cure simulation of thick thermosetting composites. Journal of Composite Materials, 25: 239-273.

14.

14. Lee, W.I. , Loos, A.C. and Springer, G.S. (1982). Heat of reaction degree of cure, and viscosity of hercules 3501-6 resin. Journal of Composite Materials, 16: 510.

15.

15. Standard test method for apparent interlaminar shear strength of parallel fiber composites by short-beam method. Designation: D 2344-2384, May 25, 1984.