Design optimization and fabrication of a lightweight leaf spring using carbon fiber,glass fiber-reinforced composites and foam core

Abstract

Leaf springs serve as essential suspension elements; however, their steel construction contributes to a higher unsprung mass, ultimately diminishing overall efficiency. This investigation examines composite leaf springs as a lighter option, providing enhanced strength-to-weight ratio and performance. The findings underscore the ability to improve ride quality and decrease energy usage, positioning them as a feasible alternative to traditional steel springs. This paper presents the proposal and fabrication of a hybrid composite for the master leaf spring structure. Identifying and simplifying hybrid composite for the master leaf spring structure with well-balanced combination of high tensile strength, toughness, and lightweight properties. These springs incorporate carbon fiber, glass fiber, and Lantor Soric XF cores, providing impressive strength-to-weight ratios and outstanding fatigue resistance while minimizing weight. An integrated AHP-TOPSIS and FEA methodology was employed to enhance the optimization of composite leaf springs. The final laminate is composed of Carbon Fiber (−82°, 1 mm), Glass Fiber (−55°, 0.75 mm), Lantor Soric XF (0°, 2 mm), Glass Fiber (+55°, 1.25 mm), and Carbon Fiber (+82°, 1 mm), determined by performance parameters such as equivalent stress and equivalent elastic strain. This investigation assesses the tensile and flexural properties. The tensile testing conducted according to ASTM D3039 indicated a UTS of approximately 23.5 MPa and a yield strength of around 8.38 MPa. The flexural testing conducted in accordance with EN ISO 14125 revealed a peak load of 0.270 kN and a transverse strength of 89.32 N/mm². The findings indicate outstanding strength-to-weight characteristics, validating the composite’s appropriateness for lightweight, load-bearing applications. The hybrid carbon–glass–foam laminate demonstrates a well-rounded combination of strength, toughness, and lightweight characteristics, positioning it as an excellent substitute for steel in automotive applications where weight is a critical factor, such as in leaf springs.