Tensile, flexural, and vibration analysis of <scp>MWCNT</scp> ‐basalt sandwich composites for car bonnet utility

Abstract This study explores the potential of sandwich plates (SPs) with basalt fiber laminated composite face layers and a polyethene terephthalate (PET) foam core, enhanced with varying weight percentages of multiwalled carbon nanotube (MWCNT) contents (0%, 0.1%, 0.3%, 0.5%, and 0.7%), for car bonnet applications. The face layers were fabricated using the hand layup technique, and the material properties of the MWCNT‐enhanced composites and PET core were characterized through uniaxial tension and compression tests. Numerical simulations in ABAQUS employing 3D solid elements (C3D8R) were conducted to predict dynamic responses, validated through experimental modal analysis (EMA) using impact hammer testing in Pulse Lab software. Flexural behavior was assessed via three‐point bending tests, demonstrating optimal mechanical performance at 0.5% MWCNT loading, with peak flexural modulus, strength, toughness, and interlaminar shear strength (ILSS). Higher MWCNT concentrations led to diminished properties. These findings offer critical insights for designing lightweight and high‐performance hybrid composite structures suitable for automotive bonnet systems. Highlight The flexural and dynamic responses of MWCNTs‐basalt skins/PET foam core‐based sandwich plates. Tensile and flexural responses increase up to 0.5 wt% of MWCNTs. Experimental modal analysis is performed for free vibration analysis. The proposed laminated composite is designed to enhance the utility and performance of car bonnets.