Agha Inya Ndukwe
@futo.edu.ng
Department of Materials & Metallurgical Engineering, School of Engineering and Engineering Technology
Federal University of Technology, Owerri, Nigeria
RESEARCH INTERESTS
Corrosion inhibition, Composites, Casting
Scopus Publications
Scopus Publications
Agha Inya Ndukwe
Engineering Society of Corrosion
This paper concerns the overview of previous studies on the corrosion and inhibition of carbon steel that is allowed to degrade in a corrosive medium by the extract of the eucalyptus plant, with an emphasis on the extract's adsorption behaviour. Many researchers have largely employed eucalyptus plant bark, oil, and leaf extracts to prevent the corrosion of mild steel in acidic environments under various temperature settings. According to the results, when the bark extract of the eucalyptus plant was added to HCl (5%) at a concentration of 900 ppm, the inhibitor's maximum efficiency was 98.2 %. The leaf extract, on the other hand, had the maximum inhibitory efficacy of 93.09 % at 600 mg/L extract concentration in the H2SO4 (0.5 M) medium. The extracts' potency was shown to diminish with increasing temperature. The mechanism for eucalyptus extract's protection of carbon steel from corrosion in diverse corrosive situations was largely associated with the adsorption of the extract's inhibitive components on the steel's surface to reduce the interaction between the metal and the corrosive surroundings. The majority of the reported inhibitive behaviour of the eucalyptus extract was consistent with the Langmuir adsorption isotherm model.
Agha Ndukwe
National Library of Serbia
This study examined the previous research on the mechanical properties of reinforced composites of aluminium-matrix, manufactured by stir casting. Stir casting has been reported as the most economical fabrication method currently in use for producing Aluminum Matrix Composites because of its accessibility, portability, adaptability to be utilized for large-scale manufacture, and easy operation of the application to conventional shape casting foundry procedures. Apart from the minority report that recorded a reduction in ductility, yield strength, ultimate tensile strength, and modulus of elasticity but with an increase in hardness of the SiC particulate reinforced aluminium matrix composites following the increase in reinforcing material, the majority of work has shown that the mechanical properties increase with the increase in the addition of the reinforcing material. Reinforcing materials like silicon carbide, tungsten carbide, alumina, boron carbide, and multi-walled carbon nanotubes have been used in various compositions to manufacture aluminium-matrix composites. The highest reported ultimate tensile strength of 489 MPa was obtained after stir casting 10 vol% of SiC - aluminium matrix composite. The maximum tensile strength of 401 MPa was attained with 20% B4C - Al-matrix composite. Various uses of metal-matrix composites have been identified in the making of hypersonic aircraft, sporting equipment, and automobile engine parts.
Agha Ndukwe, Chukwudike Onuoha, Chioma Njoku, Nsikan Dan, and Justus Anaele
National Library of Serbia
This review covers previous work by different scholars on welding polymer-matrix composites to aluminium alloys between 2015 and 2021. The highest tensile shear stress measured for the joint between polymer-matrix composite and aluminium (AA7075) alloy was 59.9 MPa. Welding using top-thermic friction stir was the method that produced the desired outcome. Additionally, the aluminium (AA2024) alloy and fibre-reinforced polymer composite were joined using an ultrasonic metal welding procedure, which produced a weld with a high tensile shear strength of roughly 58 MPa. The friction-aided joining of carbon fibre-reinforced polyphenylene sulphide composites and aluminium (AA7075) alloy has been studied by researchers. A laser treatment was applied to the aluminium surface to enhance the interlocking between the two materials being combined. This development was reported to cause inadequate bonding between the polymer-matrix composite and the metal. Despite this, the joints demonstrated significant load-bearing capacities of up to 10.7 kN.
Agha Ndukwe, Dan Etim, Anaele Uchenna, Ozoh Chibuike, Kooffreh Okon, and Paulinus Agu
Centre for Evaluation in Education and Science (CEON/CEES)
This study examined earlier research on using papaya and neem extracts as inhibitors to minimize the corrosion of mild steel in a variety of corrosive situations. The potential inhibitory characteristics of plant extracts to potentially replace the hitherto used, well-known inhibitors that are harmful to the people handling them as well as the environment, inspired several scholars to conduct corrosion inhibition tests on metals using plant extracts. The findings of earlier research demonstrated that the maximal inhibitory efficiency provided by neem leaf extract to prevent the degradation of carbon steel in a hydrochloric acid (1 M) medium was 97%, while 86% was observed for the protection in H2SO4 (1 M) solution. The extract from Carica papaya leaves was shown to have up to 83% maximum inhibitory efficacy for preventing mild steel corrosion in HCl (1 M). It has been revealed that when extract concentration increased, the rate of steel corrosion reduced. Additionally, papaya leaves' corrosion-inhibiting mechanism was said to occur mostly in the cathodic area. Both plant-leaf extracts (Papaya and Neem) have been reported to have adsorption qualities that, for the most part, agreed with the Langmuir adsorption isotherm model.
Anyanwu K.O, Anyakwo A.N, Ndukwe A.I, Chukwudike O, and Chukwudi A.P
Asian Research Association
In this paper, effort has been made to determine the durability of polyurethane coating on mild steel in acid, alkaline and neutral soil. A total of 42 mild steel coupons were used. Out of the 42 coupons, 21 were coated with polyurethane and the remaining 21 were left uncoated. Acid soil (pH = 4.5), Alkaline soil (pH =13.5) and neutral soil (pH = 6.8) were used as the test media. Seven each of the coated and uncoated coupons were buried in each soil media. On weekly basis, one coated and one uncoated coupon were withdrawn from each of the soil media and reweighed. The durability of the coating in each soil media was calculated using a proposed model. From the results obtained, the durability of polyurethane coating was found to be 7.0yrs, 4.5yrs and 2.9yrs in neutral, acid and alkaline soil respectively.