Application of hybrid AHP-TOPSIS technique in analyzing the braking performance sensitivity of organic-ceramic fibrous reinforced friction composites

In this research work, brake pad friction composite materials based on binary and ternary combinations of ceramic-organic fibres have been realized, following evaluation of braking performance parameters on Krauss friction testing machine adopting ECE R-90 regulations and PVW-32 standard test protocol.  The obtained experimental performance data has been further used for the assessment of performance based ranking using hybrid AHP-TOPSIS technique.  The order of relative weights or priority order of performance defining criteria as obtained by AHP is µ-Performance (µp) ~ Stability Coefficient (α) > % µ-Recovery > Wear (g) > % µ-Fade > DTR (°C) > Friction Fluctuations (∆µ) > Variability Coefficient (γ). The consistency verification highlights that λmax = 8.0391, consistency index = 0.0045579, and consistency ratio (CR) = 0.00323 << 0.1 (upper bound limit for acceptance of CR). The aramid fibre 5-7.5 wt.% in combination with other fibres 25-22.5 wt.% (for binary combination) and 12.5/12.5 - 11.25/11.25 wt.% (for ternary combinations) has been found to impart the best overall performance level relative to other combos of the friction composites under investigation. The sensitivity analysis of performance defining criteria's and ranking orders of the compositions in the respective formulations gives robust/stable observations as the weights changes from ± (10-20)%. The hybrid AHP-TOPSIS technique in-conjunction-with sensitivity analysis might sever as an effective tool in the decision making whenever there are finite material alternatives and finite performance determining criteria having conflicting nature.