目的 制取微弧氧化复合膜，探讨TC4钛合金微弧氧化膜层的形成温度。方法 采用在微弧氧化电解液中分别加入第二相颗粒（α-Al2O3、ZrO2、W）的方法，制得相应的TC4钛合金微弧氧化复合膜，利用第二相颗粒是否发生溶解相变来探测膜层形成的最高温度。结果 在微弧氧化复合膜中均发现了第二相颗粒，α-Al2O3、ZrO2和W粉颗粒均发生了溶解，小尺寸的第二相颗粒在膜层中全部溶解，大尺寸颗粒由于动力学的原因，熔池作用的时间很短，颗粒来不及全部溶解，仅发生了表壳和棱角的溶解，导致大颗粒的尺寸变小，轮廓变得更加圆润。在中粒径为50 nm的W粉制作的复合膜层中，并未发现W粉颗粒的存在，但是W元素均存在于膜层中。这是因为W粉颗粒太小（仅50 nm），颗粒在膜层中全部溶解。在中粒径为1 μm的W粉颗粒制作的复合膜中，发现了W粉颗粒，颗粒轮廓圆润，尺寸小于1 μm。这是颗粒部分溶解的缘故（仅表壳和轮廓发生了溶解）。在复合膜中，不含有第二相颗粒的区域均能相应地检测到Al、Zr、W元素的存在。结论 根据SEM和EDS检测结果可以得知，微弧氧化膜层形成的过程中，熔池形成的最高温度超过了W的熔点3410 ℃。

The work aims to study the formation temperature of micro arc oxidation film on TC4 titanium alloy by preparation of micro arc oxidation composite film. The micro arc oxidation composite film on TC4 titanium alloy was prepared by adding the second phase particles (α-Al2O3, ZrO2, W) in the micro arc oxidation electrolyte. The maximum temperature of the film formation was detected by the fusion of the second phase particles. The second phase particles were found in the micro arc oxidation composite film. The particles of α-Al2O3, ZrO2 and W powder were all dissolved. The small second phase particles were dissolved in the film completely. However, the large size particles are not completely dissolved due to dynamics and short operation time of molten bath. The size of large particles became smaller and the outline became more rounded because of dissolution of surface and edge. In the composite film prepared by W powder with medium particle size of 50 nm, W particles were not found, but W element was found. The particles of W powder could be dissolved completely in the film due to small size. In the composite film made of W powder with medium particle size of 1 μm, particles of W powder were found and the particles were more rounded and smaller than 1 μm. This was caused by dissolution of partial particles (only dissolution of surface and profile). In the composite film, Al, Zr and W elements could be detected in the region without the second phase particles. According to the results of SEM and EDS, the maximum temperature of molten bath exceeds the melting point of W 3410 ℃ in the process of micro arc oxidation film formation.