Performance optimization and reliability analysis of CFRP adhesive‐rivet hybrid joint

Abstract This study investigates the adhesive‐rivet hybrid joining technique between carbon fiber reinforced polymer (CFRP) laminates and aluminum alloy sheets, aiming to enhance connection performance in lightweight automotive structures. By employing a synergistic approach that integrates experimental and theoretical analyses, the research systematically examines the effects of lap length, adhesive layer thickness, and rivet length on joint performance. A regression model was developed to derive a second‐order response surface equation relevant to these variables. Comprehensive testing and high‐precision fitting analyses validate the model's robust predictive capabilities. Additionally, interaction analyses involving both single and dual factors were conducted to further confirm the model's reliability and generalizability. A surrogate model coupled with the elite non‐dominated sorting genetic algorithm (NSGA‐II) algorithm was employed for multi‐objective optimization, resulting in significant enhancements in both failure load and energy absorption values. Post‐optimization, the hybrid joint exhibited an 8.48% increase in failure load and a 14.22% improvement in energy absorption value compared to pre‐optimization levels. Experimental validation confirmed that the performance of the optimized joints fell within an acceptable error margin relative to the predictions. Reliability analysis, utilizing the Kriging model and the optimal Latin hypercube design method, demonstrated the high reliability of the optimized process. This analysis further validated the effectiveness of the optimized hybrid joints. This research provides both theoretical and practical insights into hybrid connections between CFRP and metal materials, thereby crucially improving the reliability of structural connections. Highlights The impact of joint geometry on hybrid CFRP‐AL connection performance was studied. Synergistic effects of lap length, adhesive layer thickness, and rivet length were identified. Hybrid joint durability was improved and failure risks through optimization were reduced. Optimized parameter interactions significantly improved joint reliability to 97.1%. Optimized hybrid joints increased failure load by 8.48% and energy absorption value by 14.22%.