ENHANCED DRY SLIDING TRIBOLOGICAL AND MECHANICAL PERFORMANCE OF EPOXY HYBRID NANOCOMPOSITES REINFORCED WITH MWCNTs AND NIOBIUM MXENE

Abstract

The development of multifunctional polymer nanocomposites with enhanced mechanical, tribological and electrical performance is a significant challenge for advanced engineering applications. The epoxy-based hybrid nanocomposites reinforced with functionalized multi-walled carbon nanotubes (FMWCNTs) and niobium-based MXene (Nb2CTx) were systematically investigated to establish strong structure–property relationships in this study. A series of composites (ECnNx1–ECnNx5) was prepared by incorporating the hybrid fillers in different weight fractions and their performances were evaluated in terms of tensile, microhardness, dry sliding wear and electrical conductivity analysis. The results indicate that the one-dimensional MWCNTs and two-dimensional Nb2CTx nanosheets have a strong synergistic interaction, which significantly enhances the performance. Among these compositions, ECnNx3 exhibited the optimum properties with a maximum tensile strength of 68.54 MPa, which is about 90% higher than that of neat epoxy. Tribological analysis showed a considerable reduction in wear rate as much as 84 % at lower loads and stable performance was observed under increased loading conditions. The maximum value of microhardness was 56 HV, which shows an increased resistance to local deformation. Electrical conductivity results confirmed the formation of an effective percolation network facilitating the enhanced electron transport. Morphological analysis of the worn and fractured surfaces indicated a brittle to ductile transition and identified mechanisms such as crack deflection, fiber bridging and tribofilm formation as contributing factors to improved performance. However, the addition of too much filler resulted in agglomeration and reduced efficiency.