Role of nanofiller additions on mechanical and dry sliding wear behavior of epoxy nanocomposites

Abstract

Epoxy composites reinforced with organo-modified montmorillonite (oMMT) and alumina (Al2O3) particles were prepared by incorporating nanoparticles into epoxy via high shear mixing followed by liquid molding. The effects of loading of nanoparticles on the mechanical and wear properties were studied. The results showed that the incorporation of nano-Al2O3 with nano-oMMT could effectively enhance the tensile properties of the composites. The tensile strength decreased and Young’s modulus of the epoxy increased with the increasing nano-oMMT content. The enhancement effect of the nanoparticles was more significant in the hybrid reinforced composites. The compounding of the two fillers also remarkably improved the wear resistance of the composites under higher load. The average coefficient of friction also decreased in Al2O3 filled oMMT-epoxy hybrid composite. It was revealed that the excellent wear resistance of the oMMT+Al2O3-epoxy hybrid composite was due to a synergistic effect between the oMMT and Al2O3. Nano-Al2O3 carried the majority of load during the sliding process and prevented severe wear of the oMMT-epoxy. Further, the specific wear rates of the hybrid composites decreased with the increasing applied load and sliding distance. Nanoparticles distribution and their influence on properties were emphasized. Different wear mechanisms were observed on the worn surfaces of the composites, including pitting, micro-and/or macro-cracks, as well as crack propagation of the matrix in the transverse direction.

Keywords

• Hybrid nano composites, mechanical properties, wear, wear mechanisms

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