Study on the Fabrication of Large T-shaped Composite Components Using a Random Vibration–Microwave Curing Process

Abstract The application of carbon fiber reinforced polymer composites in aerospace structures is becoming more and more extensive, but the traditional autoclave curing process for curing large components is still high energy consumption and high cost. Microwave curing has the advantages of rapid heating and high energy efficiency, but the lack of sufficient external pressure often leads to unacceptable porosity in thick or complex parts. In order to overcome this limitation, a random vibration-microwave (V-M) curing process was introduced in this study. By comparing the porosity and the mechanical properties of the T-shaped composite components cured via vibration-microwave(V-M) process and the autoclave process (0.6 MPa), this paper demonstrated the feasibility and effectiveness of the vibration-microwave process in manufacturing complex composite component. Ultrasonic C-scan results indicated that the voids in the T-joint produced by the V-M process are dispersed, and the porosity was less than 1%. Furthermore, pull-off tests showed that the T-joints produced by the V-M process exhibit superior interlaminar shear strength (ILSS). The reason for this improvement is that the vibration field enhances the resin impregnation of the fiber bundles, leading to the formation of continuous inter-fiber resin bridges and thereby improving the load transfer capability.