Nowadays, due to their unique properties and low costs, aluminum-basedalloys play a significant role in modern world. These metals which enjoy excellent properties such as high durability, malleability, lightweight and ductility are widely used in various industries such as electronics, car manufacturing and nanocomposite coatings.
Hamid Reza Masiha, one of the researchers of this project maintains that the presence of nonresistant elements such as Mg, Si, Cu and also tiny pores in aluminum-based alloys make them vulnerable to corrosion and reduce their mechanical properties. To solve this problem, a nano coating was developed to protect the aluminum alloys.
He further added: “In this research project, the effect of surface mechanical attrition treatment (SMAT) was studied on characteristics of the coatings formed using plasma electrolyte oxidation (PEO) on AA1230 aluminum. To do so, first, the samples were coated with and without SMAT pre-process. Coating by PEO method was carried out in two phosphate-based and silicate-based suspensions of silicon nitride nanoparticles for 10 min. Next, to study the distribution of the nanoparticles and elements inside the coating, surface morphology of the samples was examined using scanning electron microscopy and energy dispersive spectroscopy. In addition, wettability test was performed on all samples using the deionized water. Also, droplet expansion manner on the porous oxide coating surface and its relation with fine structure of the coating was investigated. The results indicated that samples coated in silicate-based electrolyte have a relatively rougher microstructure as compared to samples coated in phosphate-based electrolyte. The average surface pores area percentage of the samples coated in silicate-based electrolytes was 13.9% greater than that of samples coated in phosphate-based electrolyte. Moreover, the average height to diameter (h/d) value obtained from wettability test for samples coated in silicate-based electrolyte was 13.3% greater than that of phosphate-based electrolyte.
The results of this research project carried out by Hamid Reza Masiha, Hamid Reza Bagheri, MortezaGheytani, three graduate students of materials sciences, and faculty members of TMU, namely Dr. Khazraee, Dr. Sabour and Dr. Shahrabi, was published in volume 38, No. 4. of Bulletin of Material Sciences (2015) pp 935-943.