Investigation of fire resistance and thermal wear behavior of chopped basalt and glass fiber reinforced epoxy composites

This study investigates the incorporation of glass and basalt fibers into an epoxy matrix at weight fractions of 0.4, 0.8, and 1.6 wt% to enhance the fire resistance and high-temperature wear performance of epoxy resins. The fire behavior of the resulting composites was evaluated using UL-94 vertical burning and Limiting Oxygen Index (LOI) tests, while their thermal wear performance was examined over the temperature range of 25–100°C. The Shore-D hardness of neat epoxy was 77.6, which increased to 83.9 and 85.9 with the addition of 1.6 wt% glass and basalt fiber reinforcements, respectively. At 100°C, neat epoxy exhibited a volume loss of 821.14 mm 3 , whereas this value decreased to 615.8 mm 3 with glass fiber reinforcement and to 527.36 mm 3 basalt fiber reinforcement. The average friction coefficient decreased from 0.758 to 0.582 and 0.535, respectively. The Archard wear coefficient decreased from 6.66e-03 for neat epoxy to 4.36e-03 for glass-fiber-reinforced composites and to 3.35e-03 for basalt-fiber-reinforced composites. In terms of fire behavior, the LOI value increased from 25.8% for neat epoxy to 28.5% and 30.4% for glass- and basalt-fiber-reinforced composites, respectively. In the UL-94 tests, neat epoxy could not be classified, whereas glass fiber-reinforced composites achieved V2–V1 ratings, and composites containing 0.8 and 1.6 wt% basalt fiber exhibited a V0 classification. This superiority is attributed to the higher melting/softening temperature of basalt fiber and its thermally insulating aluminosilicate structure. The combined evaluation of TG/DTG, DSC and LOI results demonstrates that basalt fiber enhances the thermal stability of epoxy.