Electromagnetic wave absorbing properties of Short carbon fiber/Bismaleimide foams Metamaterial

The development of broadband electromagnetic wave absorbing materials often faces challenges due to constraints such as thickness and mechanical integrity. To address these issues, this study has engineered and fabricated a Short Carbon Fiber (SCF)/Bismaleimide (BMI) foam Metamaterial (MM). This composite is composed of a crosshatch metal pattern, reinforced with glass fiber plastic (GFRP), and a BMI foam matrix infused with SCF as a functional filler. The electromagnetic field distribution and input impedance analysis indicate that the crosshatch metal pattern is adept at modulating the impedance of the SCF/BMI foam, thereby influencing the field distribution. This material demonstrates superior absorption characteristics, with reflectivity levels below −10 dB across the 5–18 GHz frequency range, achieved with a mere 4.7 mm thickness. Moreover, the designed material maintains outstanding performance even under oblique incidence, and it exhibits commendable thermal stability and mechanical robustness. The findings suggest that the proposed SCF/BMI foam MM has promising potential for applications in radar stealth technology for various targets.