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在流速为3.5米/秒,温度50℃的条件下,考验了铝合金阳极氧化膜在高纯水中的耐腐蚀性能。试验是在专门设计的动水腐蚀试验迴路上进行的。迴路设有高流速试验段和半静态试验段,以考察水速对腐蚀的影响。系统水质通过净化分路的两个离子交换器经常维持高纯度。试样经过50小时试验后出现了表面阳极氧化膜的卷皮剥裂现象。这是一种动态条件下的特殊腐蚀类型。进一步的研究表明,氧化处理工艺对膜的耐腐蚀性有显著的影响,封闭水中某些杂质的存在阻碍了氧化膜封闭过程的完善,降低了膜的耐腐蚀性。提高封闭水的纯度和延长封闭时间有助于提高耐腐蚀性。为了得到耐腐蚀性较好的氧化膜,封闭用水的比电阻必须大于3×10~5欧姆·厘米,封闭时间应在60分钟以上。
Under the conditions of a flow rate of 3.5 m / s and a temperature of 50 ° C, the corrosion resistance of the aluminum alloy anodic oxide film in high purity water was tested. The test was carried out on a specially designed hydrodynamic corrosion test circuit. The circuit has a high velocity test section and a semi-static test section to investigate the effect of water velocity on corrosion. The water quality of the system is often maintained at high purity by purifying the two ion exchangers that are shunted. After 50 hours of test specimens, the surface of the anodic oxide film peel peeling phenomenon. This is a special type of corrosion under dynamic conditions. Further studies have shown that the oxidation process has a significant impact on the corrosion resistance of the membrane, the presence of some impurities in the blocked water hinders the perfection of the oxide membrane sealing process, reducing the corrosion resistance of the membrane. Increasing the purity of closed water and increasing the confinement time help improve corrosion resistance. In order to obtain a better corrosion resistance of the oxide film, the specific resistance of the water for sealing must be greater than 3 × 10 ~ 5 ohm · cm, closing time should be more than 60 minutes.