Theoretical and experimental investigation for enhanced thermo-mechanical and microstructural behavior of glass/carbon hybrids for automotive applications

Abstract

The optimal combination of Glass (G) and Carbon fibres (C) in epoxy composites remains challenging due to the complexities in determining the maximum mechanical, thermal, and microstructural properties. This study investigates the effects of hybrid reinforcement to enhance performance for advanced engineering applications. Hand lay-up lamination method was employed in which the reinforcement was constant at 40 wt.% for all the composition. The study examined three key processing factors: (i) Reinforcement (R) with six variations of 0 wt.%, 40 wt.% G, 40 wt.% C, 10G/30 wt.% C, 10C/30 wt.% G 20G/20 wt.% C; (ii) Nature of Fibre (NF) in woven, unidirectional, and chopped forms; and (iii) Temperature (T) at 30°C, 50°C, and 70°C. Using the Taguchi optimization method, L 18 experimental samples were prepared, with tensile strength selected as the response parameter. Validation tests including microstructural, thermal and mechanical tests were conducted on the best four samples from the optimisation The experimental results identified sample R 5 NF 2 T 70 as having the highest tensile strength (160 MPa). This was corroborated by the Taguchi optimization, which also predicted R 5 NF 2 T 70 (10C/30G woven fibre cured at 70 °C) as the optimal combination. Reinforcement emerged as the most significant processing facto, followed by Nature of Fibre and Temperature. Further validation of the top four optimized samples (R 5 NF 1 T 50 , R 6 NF 1 T 70 , R 6 NF 2 T 30 , and R 5 NF 2 T 70 ) revealed that while R 5 NF 2 T 70 exhibited superior tensile strength, thermal stability, hardness and flexural strength among the selected samples. Microstructural analysis of R 5 NF 2 T 70 indicated a well-integrated composite structure. The consistent identification of R 5 NF 2 T 70 as the best overall performing composite, considering its balance of properties, suggests its suitability for high-strength applications in various industries.