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arXiv · 2005.07471

Optimization of allotropic and hardness of aluminum oxide coating by PEO

Babak Ghorbanian·Mohammad Tajally·Seyed Mohammad Mousavi Khoie·Hossien Tavakoli
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Abstract

One of the most important methods of producing materials and oxide coating is plasma electrolytic oxidation (PEO). Coatings made on aluminum in PEO method have two allotropes of $\alpha$-Al$_2$O$_3$ and $\gamma$-Al$_2$O$_3$. Coatings containing $\alpha$-Al$_2$O$_3$ have more hardness and wear resistance; therefore, the main goal of the present study is to optimize aluminum oxide allotrope for increasing the ratio of $\alpha$-Al$_2$O$_3$ in coating made with PEO method. Results of the present study shows that the optimum electrolyte compound for making highest phase of $\alpha$-Al$_2$O$_3$ has 2.9 g/lit of KOH, 1.15 g/lit of Na4P2O7, and 0.34 g/lit of NaAlO2 and ratio of highest allotropic pick of $\alpha$-Al$_2$O$_3$ to highest allotropic pick of $\gamma$-Al$_2$O$_3$ (in XRD test) in the optimum condition is 0.622 and hardness is 1648 Vickers.

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Babak Ghorbanian, Mohammad Tajally, Seyed Mohammad Mousavi Khoie, Hossien Tavakoli. 2020-05-15. Optimization of allotropic and hardness of aluminum oxide coating by PEO. https://arxiv.org/abs/2005.07471

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