volume | PIER Journals

Abstract

This paper starts with the characteristics and advantages of microwaves processing. The shortcomings of fixed frequency, typically at 2.45 GHz were also mentioned. On account of this, a newly developed variable frequency microwave (VFM) fabrication was mentioned and adopted in place of the fixed frequency process. Two cases of fixed frequency microwave processing of materials were described; the characteristics, pros and cons of each case was mentioned and commented. Two cases of processing materials using variable frequency microwave facility (VFMF) were mentioned; the advantages and limitations of each case were discussed. The microwave processing of materials provides improved mechanical, physical and electrical properties with much reduced processing time. Furthermore, variable frequency microwave processing is more superior to its fixed frequency counterpart except that the cost of the facilities of the former is much higher than the latter at this point in time but it appears that the price will drop in the coming ten years.

1. National Research Centre (NRC), Microwave Processing of Materials, Microwave Processing of Materials, 11-12, 100, 105, National Academy Press, National Materials Advisory Board, Commission on Engineering and Technical Systems, 1994.

2. Venkatesh, M. S. and G. S. V. Raghavan, "An overview of microwave processing and dielectric properties of agri-food materials," Biosystems Engineering, Vol. 88, No. 1, 1-18, 2004.
doi:10.1016/j.biosystemseng.2004.01.007

3. Thostenson, E. T. and T. W. Chou, "Micro wave processing: fundamentals and applications," Composites A, Vol. 30, 1055-1071, 1999.
doi:10.1016/S1359-835X(99)00020-2

4. Ku, H. S., E. Siores, and, and J. Ball, "Pro ductivity improvement through the use of industrial microwave technologies," Journal of Computers and Industrial Engineering, Vol. 42/2-4, 281-290, 2002.
doi:10.1016/S0360-8352(02)00026-8

5. Lee, W. I. and G. S. Springer, "Micro wave curing of composites," Journal of Composite Materials, Vol. 18, 387-409, 1984.

6. Metaxas, A. C. and R. J. Meredith, Industrial Microwave Heating, 284-285, 5-6, 1983.

7. Liu, F., I. Turner, E. Siores, and P. Groombridge, "A numerical and experimental investigation of the microwave heating of polymer materials inside a ridge waveguide," Journal of Microwave Power and Electromagnetic Energy, Vol. 31, No. 2, 71-82, 1996.

8. Wei, J. B., K. Ngo, D. A. Tucker, Z. Fathi, F. L. Paulauskas, and W. G. Johanson, "Industrial processing via variable frequency microwaves part I: bonding applications," Journal of Microwave Power and Electromagnetic Energy, Vol. 33, No. 1, 10-17, 1998.

9. Everleigh, C. A.A. C. Johnson, R. J. Espinosa, and R. S. Garard, "Use of high power travelling wave tubes as a microwave heating source," Material Research Society Symposium Proceeding, Vol. 347, 79-89, 1994.

10. Fathi, Z., R. S. Garard, M. T. DeMeuse, J. Clemens, and C. Saltiel, "Pro cessing and modelling of select PMCs using variable frequency microwave irradiation," Polym. Mater. Sci. Eng., Vol. 72, 74-75, 1995.

11. Ku, H. S.E. Siores, and J. A. R. Ball, "W elding of thermoplastic composite using microwave energy," Proceedings of CIRP International Symposium â€” Advanced design and manufacturing in the global manufacturing era, Vol. 2, 21-22, 1997.

12. Bolton, W., Materials and Their Uses, 128, 1996.

13. Schwartz, M. M., Composite Materials Handbook, 2 Ed., 6.55-56, McGraw-Hill, 1992.

14. Varadan, V. K. and V. V. Varadan, "Micro wave joining and repair of composite materials," Polymer Engineering and Science, Vol. 3, No. 7, 470-486, 1991.
doi:10.1002/pen.760310703

15. Siores, E. and P. Groombridge, "Preliminary investigations into the use of microwave energy for fast curing of adhesively bonded joints formed using engineering thermoplastics," American Ceramic Society Bulletin, Vol. 8, 437-444, 1997.

16. Paulauskas, F. L.T. T. Meek, and C. D. Warden, "Adhesiv e bonding via exposure to microwave radiation and resulting mechanical evaluation," Material Research Society Symposium Proceedings, Vol. 430, 193-206, 1996.

17. Ku, H. S., E. Siores, J. A. R. Ball, and B. Horsfiled, "P ermittivity measurement of thermoplastic composites at elevated temperature," Journal of Microwave Power and Electromagnetic Energy, Vol. 36, No. 2, 101-111, 2001.

18. Ku, H. S., E. Siores, and J. A. R. Ball, "Relationship between microwave irradiation and constituents of composites during joining process," Transactions, Vol. 7, No. 3, 41-49, 2000.

19. Ku, H. S., E. Siores, J. A. R. Ball, and M. MacRobert, "V ariable frequency microwave processing of thermoplastic composites," Plastics, Vol. 29 No. 8, No. Vol. 29 8, 278-284, 2000.

20. Ku, S. H., C. S. Chew, D. Baddeley, and C. Snook, "Fracture toughness of vinyl ester composites cured by microwave irradiation: preliminary results," Journal of Reinforced Plastics and Composites, Vol. 24, No. 11, 1181-1202, 2005.
doi:10.1177/0731684405048841

21. Ku, H. S., E. Siores, J. A. R. Ball, and M. MacRobert, "Characterisation of thermoplastic composites using variable microwave facilities configuration," Plastics, Vol. 29, No. 8, 285-287, 2000.

22. Selleys "Araldite five minute epoxy adhesive user instructions," 1 Gow Street.

23. Von Hippel, A. (ed.), Dielectric Materials and Applications, 301, 301- 425, 1995.

24. Ku, H. S., "Microwave energy effects on matrix and fibre reinforcement of composites during bonding process by microwaves," Journal, Institution of Engineers, Vol. 63, No. 4, 20-27, 2002.

25. Kung, F. and H. T. Chuah, "A finite-difference time-domain (FDTD) software for simulation of printed circuit board (PBC) assembly," Progress In Electromagnetics Research, Vol. 50, 299-335, 2005.
doi:10.2528/PIER04071401

26. Chew, W. C., "Some reflection on double negative materials," Progress In Electromagnetics Research, Vol. 51, 1-26, 2005.
doi:10.2528/PIER04032602

27. Khalaj-Amirhosseini, M., "Micro wave filter using waveguides filled by multi-layer dielectric," Progress In Electromagnetics Research, Vol. 66, 105-110, 2006.
doi:10.2528/PIER06102502

Dr. Harry Ku