Experimental Analysis of the Mechanical Properties of Carbon Foams Under Quasi-Static Compressive Loads

This article sought to determine the response of a carbon foam material derived from polyurethane foam when subjected to a quasi-static compression load. The effects of the foam pore densities and additives (solvents) on the compression strength, compressive modulus, and surface morphology of the carbon foam were investigated. In this study, three different carbon foam pore densities (20, 40, and 60 ppi) and three solvents for the phenol-formaldehyde resins that coated the polymer foam (acetone, ethanol, and methanol) were used. Carbon foams were derived from polyurethane foams by carbonization. Quasi-static compression testing was carried out using a universal testing machine. The compressive strength, compressive modulus, and relative density of these different carbon foams were computed and compared. Two-way ANOVA analyses were performed to compare the significance of solvents and pore density. These results showed that pore density and solvents significantly affected the compressive strength, compressive modulus, and surface morphology of the fabricated polyurethane-derived carbon foam. Finally, the maximum compressive strength and maximum compressive modulus were observed in carbon foam (60 ppi) with 40% methanol as the solvent. Conversely, a minimum compressive strength was observed for a 20 ppi carbon foam with a 20% acetone solvent, and a minimum compressive modulus was observed for a 20 ppi foam with 40% methanol. Lastly, the chemical composition of the polyurethane foams was investigated, and these results indicated that the polyurethane-derived carbon foam had 96% carbon atoms after carbonization.