۱- Introduction

۲- Experiments

۳- Results and discussions

۴- Conclusion

References

Abstract

Composite microwave curing technologies have been researched and given great expectations for decades to cutting down the long curing cycle and enormous energy consumption during traditional curing process. However, this good vision was stopped since the microwave can hardly penetrate and heat multidirectional carbon fiber reinforced polymer composites. In this paper, the mechanism that multidirectional composite can hardly be heated was revealed. New method was found to stimulate Vertical Penetrating Microwave (VPM) by using metal strips, and the multidirectional carbon fiber reinforced polymer composites can be heated directly. The theory and model of VPM’s heating depth of multidirectional composite were established and verified. The results indicated that 2.3 mm thickness multidirectional composite can be cured effectively by using the VPM.

Introduction

Nowadays, large amounts of carbon fiber reinforced composite parts (CFRP) have been used in aerospace field without controversy, because of its high strength, low density and long fatigue life in strict environment [1]. The traditional autoclave curing technology manufactured large amount of composite parts for aircrafts. However, the extremely long curing cycle and high energy consumption restrict its further development. For example, the curing period for one aircraft composite part may exceed 24 hours, and energy consumption is beyond 5000KW per hour for a 5m diameter, 25m long autoclave. If half of the curing period and the energy consumption can be reduced, the annual output may be double and cost for each aircraft should be reduced. In recent years, extensive work has been conducted on the quick and energy saving microwave curing technologies of composite materials. Link et al. [2] exhibited the energy saving and fast processing advantages of microwave to heating glass and carbon fiber reinforce polymer composites. Chaowasakoo and Sombatsompop [3] also showed that microwave cured composites consumed shorter cure time and had higher impact strength than the conventional thermal cured one. Thostenson and Chou [4] discussed microwave heating of composite materials and considered that the application of microwave for processing polymer composite materials had a more efficient heat transfer over traditional heat transfer method. Boey and Yap [5] reported that microwave curing was more effective than thermal heating in accelerating the reaction rates of matrix resin.