MgO micro-powder of different concentrations from 0 to 8 g L−1 was added in the electrolyte. Effects of MgO micro-powder concentration on properties of micro-arc oxidation (MAO) coating were analysed by scanning electron microscopy, energy dispersive spectrometer, X-ray diffraction, electrochemical workstation, thermal shock tester equipment, etc. The result revealed that the concentration of MgO has evident effects on the properties of the MAO coating. When MgO micro-powder increased, the oxide voltage, the coating thickness and hardness increased first and then decreased. In this case, the diameter of the hole on the coating surface also increased and more linear holes appeared. The phases mainly consist of γ-Al2O3, α-Al2O3, MgAl2O4 and Mg2SiO4. As a result, the corrosion resistance and the adhesion of the MAO coating increase first and then decrease mainly related to the surface morphologies and phase of the coating. The coating has good thermal shock resistance. The performance of micro-arc oxidation coating with MgO micro-powder was improved.
PaksoyAH, MuhaffelF, KocaM, Formation of a corrosion-resistant alumina coating in a 6061 aluminum alloy using a combination of micro-arc oxidation and sealing treatments. Materials & Technologies, 2017, 51(117): 117–121.
2.
WangJ, HuangS, HeMY, Microstructural characteristic, outward-inward growth behavior and formation mechanism of MAO ceramic coating on the surface of ADC12 Al alloy with micro-groove. Ceram Int, 2018, 44: 7656–7662. doi: 10.1016/j.ceramint.2018.01.189
3.
Zaiedah NasirN, Mohd DaudMA, BapokuttyO, Influence of heat treatment on impact, hardness and fatigue strength of 6061 aluminium alloy. Applied Mechanics and Materials, 2015, 761:484–488. doi: 10.4028/www.scientific.net/AMM.761.484
4.
LongBH, WuHH, LongBY, Characteristics of electric parameters in aluminium alloy MAO coating process. Journal of Physics D Applied Physics, 2005, 38(18):3491–3496. doi: 10.1088/0022-3727/38/18/025
5.
BostaMMSA, MaKJ, ChienHH.The effect of MAO processing time on surface properties and low temperature infrared emissivity of ceramic coating on aluminium 6061 alloy. Infrared Phys Technol, 2013, 60(5):323–334. doi: 10.1016/j.infrared.2013.06.006
6.
HuangD, ZhangXY, WuDF, Effects of rare earth (RE) additives on Performances of micro-Arc oxidation coatings formed on aluminum alloy. Adv Mat Res, 2013, 850-851:140–143.
7.
ArslanE, TotikY, DemirciEE, High temperature wear behavior of aluminum oxide layers produced by AC micro arc oxidation. Surf Coat Technol, 2009, 204(6-7):829–833. doi: 10.1016/j.surfcoat.2009.09.057
8.
KrishnaLR, SundararajanG.Aqueous corrosion behavior of micro arc oxidation (MAO)-coated magnesium alloys: a critical review. JOM, 2014, 66(6):1045–1060. doi: 10.1007/s11837-014-0952-9
9.
ShenDJ, CaiJR, GuoCH, Evolution of residual stresses in micro-arc oxidation ceramic coatings on 6061 Al alloy. Chin J Mech Eng, 2013, 26(6):1149–1153. doi: 10.3901/CJME.2013.06.1149
10.
YangHF, LiuCW, WuSJ.Effects of forward voltage on micro-arc oxidation film on 6061 aluminium alloy. Foundry Technology, 2014, 35(6):1225–1227.
11.
DongHQ, NiuZW, ZhaoDS, Effect of current density on ceramic coating prepared by micro-arc oxidation on 6061 aluminum alloy. Corrosion Science & Protection Technology, 2014, 26(2):137–142.
12.
ShenDJ, CaiJR, LiGL, Effect of ultrasonic on micro-structure and growth characteristics of micro-arc oxidation ceramic coatings on 6061 aluminum alloy. Vacuum, 2014, 99(1):143–148.
13.
QiuT, Wu XL, Jin FY, Self-assembled growth of MgO nanosheet arrays via a micro-arc oxidation technique. Appl Surf Sci, 2007, 253(8):3987–3990. doi: 10.1016/j.apsusc.2006.08.034
14.
WangP, WuT, Xiao YT, Effect of Al2O3 micro-powder additives on the properties of micro-arc oxidation coatings formed on 6061 aluminum alloy. J Mater Eng Perform, 2016, 25(9): 3972–3976. doi: 10.1007/s11665-016-2255-5
15.
WangJL, YangW, XuDP, Effect of K2TiO(C2O4)2 addition in electrolyte on the micro-structure and tribological behavior of micro-arc oxidation coatings on aluminum alloy. Acta Metall Sinica, 2017, 30(11):1109–1118. doi: 10.1007/s40195-017-0641-0
16.
JiangZH, ZengXB, YaoZP.Preparation of micro-arc oxidation coatings on magnesium alloy and its thermal shock resistance property. Rare Met, 2006, 25(3):270–273. doi: 10.1016/S1001-0521(06)60052-1
17.
ZhengHY, WangYK, LiBS, The effects of Na2WO4 concentration on the properties of microarc oxidation coatings on aluminum alloy. Mater Lett, 2005, 59(2):139–142. doi: 10.1016/j.matlet.2004.06.025
18.
WangP, WuT, PengH, Effect of NaAlO2 concentrations on the properties of micro-arc oxidation coatings on pure titanium. Mater Lett, 2016, 170:171–174. doi: 10.1016/j.matlet.2016.02.024
19.
LiHX, SongRG, JiZG.Effects of nano-additive TiO2 on performance of micro-arc oxidation coatings formed on 6063 aluminum alloy. Transactions of Nonferrous Metals Society of China, 2013, 23(2):406–411. doi: 10.1016/S1003-6326(13)62477-2
20.
WangLS, CaiQZ, WeiBK, Characterization of oxide films formed on magnesium alloys using bipolar pulse microarc oxidation in phosphate solutions. Transactions of Nonferrous Metals Society of China, 2005, 15(3):600–605.
21.
PanYK, ChenCZ, WangDG, Influence of additives on microstructure and property of microarc oxidized Mg-Si-O coatings. Ceram Int, 2012, 38(7):5527–5533. doi: 10.1016/j.ceramint.2012.03.068
22.
WangP, WuT, XiaoYT, Characterization of micro-arc oxidation coatings on aluminum drillpipes at different current density. Vacuum, 2017, 142:21–28. doi: 10.1016/j.vacuum.2017.04.038
23.
XinSG, SongLX, ZhaoRG.Properties of aluminium oxide coating on aluminium alloy produced by micro-arc oxidation. Surf Coat Technol, 2005, 199(2): 184–188.
