LIU Siqin(1995-), male, Master candidate. E-mail: liusiqin18@mails.ucas.edu.cn
The growth processes (i.e., growth rate, inward/outward growth and compositions) of micro-arc oxidation coatings formed on AZ31 Mg alloys in different electrolytes (i.e., aluminate, silicate and phosphate, respectively) were investigated. The surface and cross-sectional morphologies with elemental distribution and the cross sections of the micro-arc oxidation coatings were characterized by scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS). The phase compositions of three micro-arc oxidation coatings with different coating thickness were determined by X-ray diffraction (XRD). The corrosion resistances of the micro-arc oxidation coatings were evaluated by electrochemical measurements and hydrogen evolution test. The growth processes in different electrolytes indicate the reasons for different anti-corrosion performances of the micro-arc oxidation coatings. The results show that the growth of micro-arc oxidation coating in aluminate is mainly due to the anionic compound deposition, and the coating grows outward, and the growth of the micro-arc oxidation coatings in silicate and phosphate is mainly due to the oxidation of the substrate, leading to the coating to grow inward. It is indicated that the growth processes of micro-arc oxidation coatings with 15 μm thickness in different electrolytes result in that different corrosion resistances (i.e., AZ31-Si> AZ31-P>> AZ31-Al).
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |