Optimal Design Based on Fabricated SiC/B4C/Porcelain Filled Aluminium Alloy Matrix Composite Using Hybrid AHP/CRITIC-COPRAS Approach

Abstract

In this present study, SiC, B 4 C and waste porcelain reinforced AA7075 alloy composites are fabricated by adopting stir casting approach. Twelve formulations based on different weight percentages of reinforcers (3\xa0wt.%, 4.5\xa0wt.%, 6\xa0wt.% and 7.5\xa0wt.%.) were manufactured and afterward analysed in terms of physical, mechanical, corrosion and tribological performances. The reinforcers of less than 53\xa0μm size were consistently blended in molten AA7075 accompanied by stirring process. To identify the best suitable formulation the density, hardness, tensile strength, compressive strength, flexural strength, friction coefficient, wear and corrosion rate were fixed as selection criteria. The composite containing 7.5\xa0wt.% B 4 C (ASBP-8) exhibited the highest mechanical strength (Hardness=162 Hv; Tensile strength= 298\xa0MPa; Compressive strength= 221\xa0MPa; and Flexural strength= 267\xa0MPa), whereas wear performance (at 40\xa0N load and 1300\xa0m SD= 0.00261\xa0g; and at 5.026\xa0m/s SV and 1300\xa0m SD= 0.0231\xa0g) and coefficient of friction (at 40\xa0N load and 1300\xa0m SD= 0.536\xa0g; and at 5.026\xa0m/s SV and 1300\xa0m SD= 0.47\xa0g) remain the lowest for 6\xa0wt.% porcelain (ASBP-11) based composites. The density and corrosion rate remains lowest for the composite containing 7.5\xa0wt.% porcelain (ASBP-12).Since no single composite(ASBP-1 to ASBP-12) could merely satisfy all the desired characteristics; to this end, this study applied a novel hybrid AHP/CRITIC-COPRAS method for the selection of optimal alternative material for automotive components. The weight of each material evaluated was determined by establishing a criterion of importance by applying inter-criteria correlation (CRITIC) and analytic hierarchy process (AHP) methods. The alternative ranking was evaluated using the complex proportional assessment (COPRAS) method. The evaluation indicated that the AA7075 containing 7.5\xa0wt.% porcelain (ASBP-12) composite possesses the best material solution to be used in automotive applications.