Publication details
A transition from petal-state to lotus-state in AZ91 magnesium surface by tailoring the microstructure
| Authors | |
|---|---|
| Year of publication | 2020 |
| Type | Article in Periodical |
| Magazine / Source | Surface and Coatings Technology |
| MU Faculty or unit | |
| Citation | |
| Web | https://doi.org/10.1016/j.surfcoat.2019.125239 |
| Doi | http://dx.doi.org/10.1016/j.surfcoat.2019.125239 |
| Keywords | AZ91 Mg alloy; Superhydrophobicity; Petal-state; Lotus-state; beta-Precipitates; Chemical etching |
| Description | This study explores the microstructural tuning of the AZ91 magnesium alloy subjecting to different heat-treatment procedures to produce the superhydrophobic surface with different adhesive properties. In this regard, a two-step chemical etching process was used to form hierarchical nano/microstructure, during which various phases were corroded with different rates. The surface morphology of samples was characterized using fieldemission scanning electron microscopy (FE-SEM) equipped with energy dispersive spectroscopy (EDS) and confocal laser microscopy (CLSM). In addition, the power spectral density (PSD) analysis was employed to evaluate the nano-scale and micro-scale components of the surfaces. The results revealed that the preferential dissolution of the matrix in favor of primary precipitates during etching treatment formed a hierarchical nano/microstructure on the surface of as-cast AZ91 sample and provided petal-type superhydrophobicity. Employing a combination of annealing and aging treatments resulted in a transition from petal to lotus-type superhydrophobicity by redistributing of the beta-precipitates in the alpha-Mg matrix. The mechanism of this transition was discussed in detail, and a direct correlation between the microstructure and the wettability behaviors of AZ91 Mg alloy was established. |