The structural and phase transformation of microarc oxidation (MAO) coatings on 6061 aluminum alloy at 300∘C/3[Formula: see text]MPa steam were evaluated. After 10 days steam corrosion, the weight loss of coated alloys with 15[Formula: see text][Formula: see text]m and 75[Formula: see text][Formula: see text]m thickness was only about 1/10 and 1/50 of weight gain of bare alloy, respectively. The [Formula: see text]-Al2O3 and [Formula: see text]-Al2O3 phases in the MAO coatings were stable at 300∘C/3[Formula: see text]MPa steam, but many fine needle-like or brick-like boehmite crystalline particles also appeared on coating surface. The boehmite had a large influence on the permittivity of coatings at low frequency. The MAO treatment on 6061 aluminum alloy improved its corrosion resistance at high-temperature and high-pressure steam.

中文翻译：

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300℃/3 MPa蒸汽条件下6061铝合金微弧氧化涂层的高温蒸汽腐蚀

6061铝合金在300℃微弧氧化（MAO）涂层的结构和相变∘C/3[公式：见正文]MPa蒸汽进行了评价。蒸汽腐蚀10天后，15[公式：见文][公式：见文]m和75[公式：见文][公式：见文]m厚度的涂层合金的重量损失仅为1/10左右，分别为裸合金增重的 1/50。[公式：见正文]-Al2○3和[公式：见正文]-Al2○3MAO 涂层中的相稳定在 300∘C/3[式：见正文]MPa蒸汽，但涂层表面也出现许多细小的针状或砖状勃姆石结晶颗粒。勃姆石对低频下涂层的介电常数有很大影响。6061铝合金经MAO处理提高了其在高温高压蒸汽下的耐腐蚀性能。