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Corrosion of copper occurs when it is exposed to the atmosphere and oxidizes, causing bright copper surfaces to become dull and discolour. After a few years, it slowly changes to dark brown and finally green. In this study, the copper plate was coated with cobalt-nickel-iron (Co-Ni-Fe) alloy using electrodeposition in a hull. The process was done for 15 min using platinized titanium as the anode and the copper plate as cathode. The electrolyte was sulphate solution and the working temperature was 50 °C. This method allows a variation of thickness, microhardness, morphology and composition of the coating which were influenced by different local current density. Multiple tests were conducted to obtain the desired properties of the coating using 3D surface metrology system, Vickers microhardness tester, and scanning electron microscope (SEM). The copper plates had uniform coating of Co-Ni-Fe at the surface under the examination of SEM. In conclusion, the thickness and microhardness of coating increase when the current density increases. Furthermore, this method improved the mechanical properties of the copper plate because the microhardness of the coating was 285.3 HV compared to 126.4 HV of the copper plate. Some voids and agglomerates were found on the surface of the coating when deposited at low and high current density. The desirable surface morphology was obtained at 32.29 mA/cm2 but with a trade-off having moderate microhardness.

Corrosion has been acknowledged as one of the biggest opponents in applications and industries such as in motorized industries, oil and gas industries, manufacturing and chemical plants, electric power generation plants and concrete structuresUsing the electrodeposition process, Cobalt-Nickel-Iron (CoNiFe) nanocrystalline coatings were successfully synthesized onto mild steel fasteners (bolt and washer) with deposition times of 15, 30, and 45 minutes, respectively. The objective of this research is to study the corrosion behaviour of the CoNiFe coated onto the mild steel fasteners. The electrodeposition process was performed by controlling its operating parameters such as temperature, pH, current density, deposition time and electrolyte composition. The temperature used throughout the process was 50 °C in an acidic condition of pH 3. By varying the deposition times, the phase and crystallographic structure, surface morphology, grain size, microhardness, and surface roughness of the CoNiFe coatings were examined. Based on the FESEM micrographs, the grain sizes of the coatings were in the range of 85.34 nm to 95.01 nm. Dendrite and irregular shapes were observed for the microstructure of CoNiFe nanocoating. The CoNiFe nanocrystalline coating prepared with a deposition time of 45 minutes achieved the highest microhardness of 228 HVN. The surface roughness also increases with longer deposition time. It was found that by increasing the deposition time also enhanced the microhardness and magnetic properties of CoNiFe nanocoating. From the salt (fog) spray test, the longer deposition time used had the highest corrosion resistance. Thus, it can be concluded that the optimum deposition time of the electrodeposited CoNiFe coating on the mild steel fasteners was 45 minutes which produces optimum properties.

This research is to develop the natural Activated Carbon (AC) composites prepared from carbon coconut shell reinforced with polypropylene (PP). Carbon coconut shell were selected from in-productive of coconut shell specifically namely as carbon Komeng coconut shell (CKCS) with different weight percentages of AC (6, 4 and 2wt%) and PP (4, 6 and 8wt%) contents. The specimens were then encapsulated with epoxy resin. The entire specimens were prepared using SRM (Silicon Rubber Moulds) with dumbbell shape and rectangular shape according to the standard ASTM D2099 and ASTM D256 respectively. The mechanical properties of all samples were investigated to characterize the quality of the samples. The morphological studies of reinforced samples were observed by using SEM machine. The results showed that the tensile stress was increased when AC is increased specifically for sample 4 wt% and 8 wt%. Maximum tensile stresses lead by sample 4 wt% with 30MPa.