Corrosion Resistance of Al-Si-Mg/SiC Composite in Inoculated Oily-HCl Solution
Authors: Asuke F, Musa AA, Abdulwahab M, Yaro SA, Aliyu M
The influence of Jatropha curcas oil on the corrosion resistance of Al-Si-Mg/SiC composite in 0.5HCl solution was investigated using weight loss method. Al-Si-Mg with SiC (equivalent to 10% of the total weight of the molten metal) was produced and cast into cylindrical test bar of length 30cm and diameter of 1.5cm. After casting, the bars were cut into coupons of 15 × 10 mm dimension for corrosion test. They were immersed in 0.5M HCl with and without Jatropha curcas oil in order to determine the corrosion rate. The study was carried out at different Jatropha curcas oil concentrations; 1.5, 3.0, 4.5, 6.0 and 7.5%v/v, and varying exposure time and temperature. The result obtained revealed that Jatropha curcas oil was able to reduce the corrosion rate of Al-Si-Mg/SiC at a concentration of 7.5%v/v at room temperature. The inhibition was attributed to the adsorption of Jatropha curcas oil onto the surface of the composite at room temperature which prevents the breakdown of the passive film, hence, preventing the corrosion of the composite (Al-Si-Mg/SiC). Furthermore, the microstructure contains thin layers of the inhibitors molecules which protect the metal against corrosion attack at room temperature.
Affiliations: Department of Metallurgical and Materials Engineering, Ahmadu Bello University, PMB 1045, Zaria, Nigeria
Keywords: Jatropha Curcas Oil, Al-Si-Mg/SiC Composite, Activation Energy, Thin Film, Adsorption
Published date: 2018/12/30