Advanced cenosphere-reinforced syntactic foams: focus on specific strength enhancement

This work investigated the manufacturing and mechanical properties of the cenosphere-filled syntactic foams (SF). The foams were created by mixing cenospheres with a polymer resin, which was then cured to form a solid structure. The resulting syntactic foams were evaluated using hardness, density, tensile, flexural, and Charpy impact tests. The incorporation of higher volume fractions of cenosphere led to significant weight savings and improved mechanical properties. Notably, the SF60 composition achieved a 20.39% reduction in density and a 26.15% increase in hardness compared to the neat epoxy. The study demonstrated significant improvements in the mechanical properties of the syntactic foams when compared to the neat epoxy. Specifically, the flexural modulus of SF60 was 10.63% higher compared to SF0, and an even more pronounced increase of 33.11% was observed when compared to the pure resin sample. In tensile testing, the modulus values of the foams were shown to increase by 5.53–33.83% relative to the pure resin. Furthermore, the specific modulus of the syntactic foams exhibited a substantial enhancement, ranging from 14.5% to 61.23% higher compared to the neat sample. Impact strength testing revealed that the developed foams demonstrated a significant improvement, with a 7.2–65.5% increase in impact strength compared to the neat epoxy. Moreover, the specific impact strength of the syntactic foams was found to be 13.3–100% higher than that of the neat epoxy. These findings indicated that cenosphere-filled syntactic foams not only enhanced mechanical performance but also offered significant weight reduction, making them ideal for lightweight applications where both strength and impact resistance are crucial.

Graphical abstract