Title: EFFECT OF NANO-FILLER MODIFICATION ON SINGLE-LAP SHEAR TENSILE PERFORMANCE OF GFRP COMPOSITES FOR AIRCRAFT REPAIRS

Authors: Sarabjeet Singh, Saji D, Prashant Rawat

DOI: https://doi.org/10.33599/GL.2026.INCOMAT.TP26-0020

Abstract: Metallic and Composite aircraft structures are subjected to foreign object damage (FOD), such as bird strikes, tool drops during maintenance, and ground accidents, throughout their service life. These damages require a specific field repair scheme that ensures structural integrity under mechanical loading conditions, especially to fulfil immediate operational requirements. In addition, the literature suggests that limited work on field repair schemes is a present-day challenge for field-level applications in remote operating border areas. This work presents an experimental characterization of aviation-grade structural adhesives (Araldite AV 138M & HV 998) in neat form and in filler-modified formulations containing glass micro-balloons (GMB), carbon nanotubes (CNT), and graphene at 1 wt.% reinforcement to the resin mixture. The mechanical performance under single lap shear tensile testing is calculated in accordance with ASTM D5868 to quantify tensile shear strength, stiffness, and failure behaviour. The results indicated that the neat adhesive (reference samples) exhibited an average lap shear strength of approximately 7-9 MPa. Filler-modified systems demonstrated improved performance, with CNT and graphene resulting in approximately 3% and 11% improvement in tensile shear strength, respectively, whereas GMB addition led to a reduction of approximately 21%. Failure mode analysis revealed a transition from predominantly adhesive failure to mixed and cohesive failure modes in filler-reinforced joints, indicating enhanced interfacial bonding and effective load transfer. The study establishes a quantitative baseline for the use of filler-enhanced adhesives in aircraft repair applications.

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Conference: INCOMAT 2026

Publication Date: 2026/03/13

SKU: INCOMAT.TP26-0020

Pages: 15

Price: $30.00