Optimum design based on fabricated natural fiber reinforced automotive brake friction composites using hybrid CRITIC-MEW approach

In this present study, the hybrid criteria importance through inter-criteria correlation (CRITIC) and multiplicative exponent weighting (MEW) optimization approach is applied to the problem of selecting an optimal brake friction formulation that satisfies maximum performance requirements. Automotive brake friction composites containing 5, 10, 15, and 20 weight percentages of natural fibers (hemp, ramie, and pineapple) were developed. These composites analyzed for tribological properties using a Chase testing machine following IS-2742 Part-4 standard. The tribological results, such as friction-fade (%), friction coefficient, friction-recovery (%), friction fluctuations, friction-variability, friction-stability, and wear, are fixed as performance attributes to identify the most suitable friction formulation. The performance coefficient of friction (0.548) and friction-stability (0.93) remain highest for 5 wt.% pineapple fiber composites. Whereas the lowest wear (1.08 g) along with the least friction-recovery (107.54%) was exhibited by 5 wt.% hemp fiber composites. The highest friction-recovery (121.56%) corresponding to the lowest friction performance (0.501) was exhibited by 20 wt.% ramie fiber added composite. On the other hand, 5 wt.% ramie fiber added composite display lowest friction-fade (22.12%) with least friction-variability (0.330) and fluctuation (0.178). The experimental results are found to be strongly composition-dependent and without any pronounced trend. Consequently, it becomes difficult to prioritize the performance of formulations to choose the best among a set of composite formulations. Therefore, a multi-criteria decision-based optimization approach called CRITIC-MEW was applied; that suggests 5 wt.% ramie fiber added composite satisfies the maximum preset performance criteria.