A comparative multifunctional performance assessment of borophene-coated carbon fiber composite and Aluminium 6063-T6 alloy for aerospace structures

Abstract Weight reduction remains a critical challenge in aircraft structural design due to its direct impact on fuel efficiency, emissions, and payload capacity. Aircraft structural efficiency is strongly influenced by material selection, particularly in terms of weight reduction, durability, and multifunctional performance. Traditional Aluminium alloys, while widely adopted in fuselage structures, present challenges related to mass, corrosion, fatigue, and the need for additional conductive layers when used alongside composite components. This study explores the development and assessment of a borophene-coated carbon fiber composite aimed at overcoming these limitations and advancing lightweight aircraft structural design. The proposed composite integrates borophene as a conductive and reinforcing surface layer on carbon fiber reinforced polymer (CFRP) composite, enabling enhanced mechanical, structural, and thermal performance, along with improved environmental behavior. A comprehensive experimental program was conducted, including tensile, compression, flexural (3-point bending), impact, thermal conductivity, thermal shock, corrosion, water ingress, and dry sand erosion tests, to assess the mechanical and environmental performance of the developed composites. The borophene-coated CFRP composite exhibited a high ultimate tensile strength of 929 MPa, representing an approximately 286% improvement compared to Al 6063-T6 alloy (241 MPa), demonstrating excellent load-bearing capability for lightweight structures. In compression, the composite showed a strength of 245 MPa compared to 342 MPa for Al 6063-T6, indicating efficient structural response under compressive loading. In the 3-point bending test, the borophene-coated CFRP achieved 1110 MPa, outperforming Al 6063-T6 alloy at 520 MPa, demonstrating superior flexural stiffness and strength. This study introduces a novel borophene coating on carbon fibers, enabling simultaneous enhancement of mechanical strength, thermal stability, and electrical conductivity in CFRP composites. The study provides insight into the potential role of borophene-enabled composites in future aerospace structures, supporting the ongoing transition toward lighter, more efficient, and sustainable aircraft designs.