Experimental Study on the Dynamic Behavior of Syntactic Foam under Low Temperatures

Abstract

Syntactic foam is a composite material that enhances lightweight properties by incorporating low-density microballoons into matrix materials such as metals, polymers, and ceramics. As the microballoons are typically microscale, factors such as dispersibility and air entrapment during processing can significantly affect the final quality of the composite. Originally developed as a buoyant material for offshore structures and floating platforms, syntactic foam has since found broader applications in aerospace, space, and marine insulation due to its excellent thermal insulation characteristics. To utilize syntactic foam as an effective insulation material, it is essential to examine how its physical properties change under varying temperature conditions. Prior studies have confirmed that stiffness decreases with temperature, which in turn affects dynamic characteristics such as natural frequency and damping ratio. As these properties fluctuate with both temperature and material composition, unintended vibration-induced structural issues may arise. Therefore, a precise understanding of the vibration behavior of syntactic foam is critical for the design and maintenance of structures employing it as insulation. Despite its increasing application, research on the temperature-dependent vibration characteristics of syntactic foam remains limited. In this context, the present study investigates variations in natural frequency and damping ratio over a temperature range from ambient conditions to -40°C. Experimental results confirm that both properties vary significantly with temperature, underscoring the need to incorporate temperature-dependent dynamic behavior into the structural design of syntactic foam-based systems.