Optimization on tribological properties of natural fiber reinforced brake friction composite materials: Effect of objective and subjective weighting methods

Abstract

This research aims to study the effect of objective and subjective weighting methods in multi-attribute decision-making (MADM) and then develop a systematic framework for selecting the best natural fiber-reinforced friction composite for automobile braking applications. Therefore, sixteen friction composites with varying weight amounts (5, 10, 15, and 20 wt%) of pineapple, ramie, hemp, and banana fibers were fabricated and evaluated for tribological properties. The experimental results, such as friction coefficient, fade-recovery performance, friction fluctuations, wear, friction stability, and variability aspects, were discussed and considered performance attributes for selecting optimal composition. The results indicated that the incorporation of varying amounts of natural fibers has different effects on the tribological properties, making it challenging to prioritize the performance of the composites to choose the best from the set of composite alternatives. Therefore, EDAS (evaluation based on the distance from the average solution) MADM approach has been applied to pick the best alternative from sixteen natural fiber-based brake friction composites. As an input to EDAS, different types of objective and subjective weighting methods were used to identify the importance of each attribute. These methods include the CRITIC (criteria importance through inter-criteria correlation), entropy, BWM (best-worst method), and AHP (analytic hierarchy process). The results show that the composite alternative with 5 wt% ramie fiber exhibits the optimal tribological properties. The sensitivity analysis and validation reveal the robustness of the results, demonstrating that the same alternative dominates in diverse MADM and weighting conditions.