An integrated multicriteria decision making framework for the selection of waste cement dust filled automotive brake friction composites

Our plain-English summary of An integrated multicriteria decision making framework for the selection of waste cement dust filled automotive brake friction composites, by T. Singh (Scientific Reports, 2024).

The study

• Author: T. Singh
• Journal: Scientific Reports
• Published: 2024;14(1):6817
• Cited by: 1 article, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

This work discusses selecting optimal brake friction composite alternatives based on an integrated MABAC (multi-attributive border approximation area comparison) and AHP (analytic hierarchy process) approach. Therefore, non-asbestos automotive brake friction composites containing varying proportions of cement dust (50 to 0 wt%) and barium sulfate (0 to 50 wt%) were developed and tribo-evaluated on a Krauss machine following European regulations. Composite made up of 30 wt% cement dust and 20 wt% barium sulfate had the highest friction coefficient (0.361), lowest variability coefficient (0.598), and maximum recovery (123.27%). The composite with the least fading (15.36%) included 50 wt% cement dust, whereas the composite with the lowest wear (9.10 g) and the least frictional fluctuations (0.271) contained 50 wt% barium sulfate. By AHP, the friction coefficient (0.1989), fade (0.1696), recovery (0.1551), and wear (0.1412) were selected as the essential criteria in the performance assessment. Based on the MABAC ranking evaluation, the composite comprises 20 wt% barium sulfate and 30 wt% cement dust has the best tribological profile, whereas the composites of solely cement dust or barium sulfate have the poorest tribological profile. The acquired ranking results were confirmed using other decision-making models and subjected to sensitivity analysis to demonstrate their robustness.

© 2024. The Author(s).

In plain English

This was a laboratory engineering study of brake pad materials. It was not a study of health or of asbestos exposure, and the brake composites were described as non-asbestos. The author made seven brake friction composites. Half of each mix was fixed: phenolic resin; Kevlar, steel and lapinus fibers; alumina, vermiculite and graphite. The other half was waste cement dust and barium sulfate, ranging from 50 wt% cement dust with no barium sulfate to the reverse. The cement dust came from a cement plant in Himachal Pradesh, India. The pads were tested on a Krauss machine under European rules. The composite with 30 wt% cement dust and 20 wt% barium sulfate had the highest friction coefficient (0.361) and the highest recovery (123.27%). The all-cement-dust composite had the least fade (15.36%) but the most wear (21.20 g). The all-barium-sulfate composite had the least wear (9.10 g). Using decision-making methods called AHP and MABAC, the author ranked the 30:20 composite first. A different weighting method (CRITIC) ranked another composite, CD4, first. The author concluded that the 30:20 composite displayed the most desirable tribological characteristics. Release of airborne particles was not investigated.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Laboratory materials study: brake friction composites were made and bench-tested, then ranked with multi-criteria decision-making methods (AHP weighting with MABAC ranking, checked against CRITIC, GRA, PROMETHEE and VIKOR)
• Who was studied: Seven non-asbestos automotive brake friction composites (CD1 to CD7), with cement dust from a cement industry in Himachal Pradesh, India; no people were studied
• Exposure: No human exposure was studied. The materials tested were a fixed 50 wt% of phenolic resin, Kevlar, steel and lapinus fibers, alumina, vermiculite and graphite, plus cement dust (50 to 0 wt%) and barium sulfate (0 to 50 wt%). The composites were described as non-asbestos.
• Main results:
  • The friction coefficient peaked at 0.361 for CD3 (30 wt% cement dust, 20 wt% barium sulfate).
  • The lowest friction coefficient, 0.327, was recorded for CD7 (50 wt% barium sulfate).
  • Wear was highest, at 21.20 g, for CD1 (50 wt% cement dust).
  • Wear was lowest, at 9.10 g, for CD7 (50 wt% barium sulfate).
  • Fade was lowest (15.36%) for CD1 and increased as the barium sulfate content increased.
  • Recovery was lowest (114.20%) for CD1 and highest (123.27%) for CD3.
  • The variability coefficient was lowest for CD3 (0.598) and highest for CD1 (0.673).
  • Friction fluctuations were highest for CD1 (0.329) and lowest for CD7 (0.271).
  • AHP gave the most weight to friction coefficient (0.1989), then fade (0.1696), recovery (0.1551) and wear (0.1412).
  • MABAC scored CD3 highest (0.1841), then CD4 (0.1762); CD1 scored lowest (minus 0.1888).
  • With CRITIC weights instead of AHP weights, CD4 ranked first.
  • CD3 ranked first with all of the other decision-making methods compared.
• The authors' conclusion: The author concluded that the composite with 30% cement dust and 20% barium sulfate displayed the most desirable tribological (friction and wear) characteristics, and that the AHP-MABAC results proved reliable.
• Limitations the authors state:
  • Release of airborne particles and brake squeal noise were not investigated and were left for future research.
  • AHP weights depend on the decision-makers' judgments and may be biased toward particular criteria.
  • Rankings varied depending on the decision-making method used.

Related studies

• Application of Product of Vitrification of Asbestos-Cement Waste and CRT Glass Cullet as Reinforcing Phase in Surface Composites Produced by FSP Method — J. Iwaszko, K. Kudła, et al. (2024)
• Research cost analyses to aid in decision making in the conduct of a large prevention trial, CARET. Carotene and Retinol Efficacy Trial — M.D. Thornquist, N. Urban, et al. (1993)
• Epidemiology: a foundation of environmental decision making — K.C.K. Deener, J.D. Sacks, et al. (2018)
• Understanding clinical decision-making in mesothelioma care: a mixed methods study — C. Henshall, P. Dawson, et al. (2022)
• Mesothelioma incidence surveillance systems and claims for workers' compensation. Epidemiological evidence and prospects for an integrated framework — A. Marinaccio, A. Scarselli, et al. (2012)
• History and evolution of warning labels for automotive friction products — L.M. Kopelovich, K.A. Thuett, et al. (2014)

Browse more research in Scientific Reports, or return to medical research.