为提高钛合金焊接接头的耐蚀性能，以TA2焊接接头为基体，采用微弧氧化和低能修饰相结合的方法，分别在母材区、焊缝区和热影响区制备超疏水涂层。使用金相显微镜、扫描电子显微镜(SEM)、X射线衍射仪(XRD)、傅立叶变换红外光谱仪(FTIR)表征了试样的显微组织、微观形貌和化学成分，通过电化学阻抗谱(EIS)测试了试样在3.5%(质量分数)NaCl溶液中的耐蚀性能。结果表明：微弧氧化处理获得了大脑状微米级沟槽结构，其物相组成为锐钛矿型TiO2,经过低能修饰后，3个区域的水接触角分别为154.5°、152.3°和153.6°,滚动角分别为2.9°、4.4°和3.2°,表现出良好的超疏水性。在EIS测试中，超疏水涂层的容抗弧半径最大、微弧氧化涂层的次之，二者均提高了基体的耐蚀性能，其中，热影响区超疏水试样的电荷转移电阻相较于基体的提高了近7倍，具有最佳的耐腐蚀性能。
In order to improve the corrosion resistance of welded joints of Titanium(Ti) alloy, using TA2 welded joints as the substrate, a combination of micro-arc oxidation and low-energy modification methods was used to prepare superhydrophobic coatings in the base metal zone, weld zone and heat affected zone, respectively. The microstructure, morphologies and chemical composition of the sample were characterized by metallographic microscopy, scanning electron microscopy(SEM), X-ray diffraction(XRD) and Fourier transform infrared spectroscopy(FTIR). Moreover, the corrosion resistance of the sample in a 3.5%(mass fraction) NaCl solution was tested by electrochemical impedance spectroscopy(EIS). Results showed that the substrate treated by micro-arc oxidation obtained a brain shaped micron groove structure, and its phase composition became anatase type TiO2. After low-energy modification, the water contact angles of the three regions were 154.5°, 152.3° and 153.6°, and the rolling angles were 2.9°, 4.4° and 3.2°, respectively, which exhibited good superhydrophobicity. In EIS testing, the capacitance arc radius of superhydrophobic coatings was the largest, followed by micro-arc oxidation coatings. Both types of which improved the corrosion resistance of the substrate. Among them, the charge transfer resistance of the superhydrophobic sample in the heat affected zone increased by nearly 7 times compared to the substrate, exhibiting the optimal corrosion inhibition performance.
