EFFECT OF ALUMINA PARTICLE SIZE ON THE MECHANICAL PROPERTIES AND MORPHOLOGY OF PHENOLIC/GLASS FIBER REINFORCED COMPOSITES

Abstract

In this study invesigated the effects of nano-sized (nAl₂O₃) and micro-sized (µAl₂O₃) aluminum oxide
particles on the mechanical properties and morphology of phenolic resin-based glass fiber-reinforced
composites were investigated. Experimental results indicated that both types of additives enhanced thermal
conductivity and reduced material porosity after curing. Additionally, mechanical properties such as tensile
strength, tensile modulus, flexural strength, fiber–matrix interfacial strength, and interlaminar shear
strength were all improved. Notably, the composite containing 2% nAl₂O₃ exhibited the highest tensile
strength (324.6 MPa), while 6% nAl₂O₃ yielded the greatest fiber–matrix bond strength (6.21 MPa), both
outperforming µAl₂O₃-modified samples. In contrast, the incorporated µAl₂O₃ composites showed superior
enhancements in tensile modulus, flexural strength, and especially interlaminar shear strength, with a peak
value reaching up to 35.7 MPa, a 182% increase compared to the unmodified sample. These findings
highlighted the potential of utilizing alumina particles with a various size to effectively enhance the
mechanical performance of phenolic resin-based fiber-reinforced composites