This study presents the development and systematic evaluation of novel aluminum-based metal matrix composites (AMMCs) reinforced with silicon carbide (SiC), graphite, and peanut shell ash (PSA), alloyed with copper (Cu) and magnesium (Mg), to enhance machinability, mechanical performance, and sustainability. Two hybrid composites were fabricated using stir casting: Sample A (Al-82%, SiC-5%, Cu-2%, Mg-1%, PSA-10%) and Sample B (Al-80%, SiC-10%, Cu-3%, Mg-2%, PSA-5%). The composites were characterized through microstructural analysis, tensile testing, hardness, FTIR (Fourier-Transform Infrared Spectroscopy), DSC (Differential Scanning Calorimetry), UV-Vis (Ultraviolet-Visible Spectroscopy), and XRD (X-Ray Diffraction). Machining trials were conducted under conventional and ultrasonic-assisted conditions, with machining parameters including cutting speed (A) ranging from 11 to 42 mm/min (mean: 26.51 mm/min, standard deviation: 13.22), feed rate (B) ranging from 0.05 to 0.15 mm/rev (mean: 0.098 mm/rev, standard deviation: 0.037), and depth of cut (C) varying from 0.5 to 0.95 mm (mean: 0.698 mm, standard deviation: 0.168), all treated as continuous numeric variables. Optimization was performed using Response Surface Methodology (D-optimal, reduced quadratic model) integrated with Fuzzy AHP and Intuitionistic Fuzzy MARCOS. Results indicated that Sample A exhibited superior ductility, energy absorption, and thermal stability due to the presence of bio-carbon phases, while Sample B demonstrated higher hardness, strength, and thermal conductivity attributed to refined SiC-Cu reinforcements. FTIR confirmed organic phases in Sample A and stronger inorganic bonding in Sample B, whereas XRD revealed crystalline SiC/Cu peaks in Sample B and amorphous bio-carbon in Sample A. Among machining runs, optimum performance was achieved in Run 7 (cutting speed: 42 mm/min, feed rate: 0.05 mm/rev, depth of cut: 0.85 mm, Sample B), with low surface roughness (1.118 µm), minimal tool wear (2.94 µm), high material removal rate (10.764 cm3/min), and moderate power consumption (218.05 W). ANOVA and confirmation tests validated model accuracy with less than 5% error. Overall, Sample A is recommended for lightweight, ductile applications, while Sample B is better suited for high-strength, wear-resistant components. Sample A suits lightweight autosmotive and aerospace panels, while Sample B fits wear-resistant structural parts. Future work will examine durability, corrosion, PSA chemistry, and industrial scale-up.
Sivam et al. (Wed,) studied this question.