DSpace Collection: Material and Metallurgical Engineering

Optimisation Of Stir Cast Process Parameter Of Carbon Nanotube Reinforced Aluminium Alloy Metal Matrix Composite Using Response Surface Methodology (RSM)

2026-05-05T20:02:39Z

Title: Optimisation Of Stir Cast Process Parameter Of Carbon Nanotube Reinforced Aluminium Alloy Metal Matrix Composite Using Response Surface Methodology (RSM) Authors: Yerima, M.L; Abdulkareem, A.S.; Abubakare, O. K.; Ndaliman, M. B.; Khan, R. H. Abstract: The paper presents the results of experimental investigations on tensile strength and optimization of stir casting process parameters of carbon nanotube (CNT) reinforced aluminium 2024 metal matrix composite using Response surface methodology (RSM). The effect of casting parameters such as percentage of reinforcement fraction, stirring time, stirring speed and casting temperature of Al 2024 metal matrix composite manufactured through stir cast route method was studied. An empirical model was developed for predicting the tensile strength of CNT reinforced aluminium 2024 metal matrix composite. Adequacy of the developed model was tested using ANOVA and found to have excellent predictive capacity as indicated by the values of R² of 0.8904. The optimum process conditions were established to be 1.93-% reinforcement fraction, 433.5 rpm stirring speed, 690 °C processing temperature and 150sec stirring time. At this condition, an optimal increase of 76% in tensile strength of the composite was observed using desirability function approach.

Development of Banana-Fiber Reinforced Epoxy Composite Fan Blade for Electric Motor Cooling

2026-05-05T19:25:17Z

Title: Development of Banana-Fiber Reinforced Epoxy Composite Fan Blade for Electric Motor Cooling Authors: Yerima, M.L; Alhassan, A.; Isah, M.; Godfrey, M. Abstract: - In this paper, we report the design and testing of axial cooling-fan blades fabricated from banana-fiber–epoxy composites. Five composite fans labelled (B–F) with increasing banana-fiber content (by weight) and one commercially obtained ABS plastic fan labelled A as the control. Samples B-F were manufactured by hand lay-up in a 6-blade mold. Banana fibers were NaOH-treated and used at, 10%, 20%, 30%, 40%, and 50% fiber weight fractions for samples B–F respectively. The fans blade spanning 120 mm and chord 6 mm were cured 24 h at room temperature + 2 h at 80 °C. We characterized physical (density, porosity), mechanical (tensile, flexural, impact, hardness, fatigue), thermal (thermal conductivity, specific heat), and performance metrics (airflow rate, motor surface temperature, motor power/vibration) for each sample. Tensile and flexural tests followed ASTM D3039 and D790, Izod impact per ASTM D256, hardness per ASTM D2240, and fatigue per ASTM D3479. Composites with moderate fiber fraction of 30–40 wt% showed significantly higher stiffness and heat dissipation than the control, reducing motor temperature by 10 % under full load. Statistical ANOVA confirmed significant effects of fiber content (p<0.01) on strength and thermal performance. We conclude that 30–40 wt% banana fiber yields optimal cooling efficiency and mechanical integrity. This work demonstrates the feasibility of low-cost, eco-friendly banana–epoxy fans for motor cooling.

Enhanced biocompatibility and mechanical properties in carbon nanotube-reinforced natural rubber nanocomposites: a review for biomedical applications

2026-05-04T19:16:54Z

Title: Enhanced biocompatibility and mechanical properties in carbon nanotube-reinforced natural rubber nanocomposites: a review for biomedical applications Authors: Alade, N. A.; Abubakre, O. K.; Medupin, O. R.; Abdulkareem, A. S.; Akintunde, I. B.; Mustapha, S.; Tijani, J. O.; Muriana, R. A.; James, J. A. Abstract: Carbon nanotube (CNT)-reinforced natural rubber (NR) nanocomposites represent a promising material platform for biomedical applications, particularly prosthetic systems requiring flexibility, durability, and mechanical resilience. These composites exhibit enhanced tensile strength, elasticity, and fatigue resistance, while offering improved biocompatibility when appropriately functionalised. This review examines recent advances in CNT synthesis, including chemical vapour deposition (CVD) and arc discharge methods, together with covalent and non-covalent functionalisation approaches aimed at improving dispersion and reducing cytotoxicity. Despite encouraging progress, challenges persist, including CNT agglomeration, long-term biocompatibility uncertainties, regulatory constraints, and production costs. Key research gaps are identified, including sustainable synthesis routes, standardised chronic biocompatibility evaluation, and patient-specific customisation. Addressing dispersion control, long-term safety validation, and scalability will be essential for establishing CNT-NR composites as next-generation materials for durable, multifunctional prosthetic devices.

Synthesis of CNTs via Chemical Vapor Deposition of Acetylene as a Carbon Source in the Presence of Co-Mo/MgO Catalyst

2026-05-03T18:34:09Z

Title: Synthesis of CNTs via Chemical Vapor Deposition of Acetylene as a Carbon Source in the Presence of Co-Mo/MgO Catalyst Authors: Yerima, M.L; Abdulkareem, A.S.; Ndaliman, M B.; Khan, H. R. Abstract: Varbon nanotubes were synthesized via the chemical vapor deposition (CVD) method, using Co-Mo/MgO as a catalyst and C2H2, abundant and economical carbon source. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM), along with the results from x-ray diffraction (XRD) analysis confirmed the successful formation of MWNTs. The bimetallic catalyst was found to produce MWCNTs of 218% with BET surface area of 289m2/g. The average length and diameter were found to be 33um and 32nm. The study has demonstrated that high quality MWNTs can be obtained from Co_Mo/MgO catalyst via wet impregnation followed by CVD technique.