Alkali resistance test is a professional test method specially used to test the corrosion resistance of aluminum oxide film. In this method, a 10% potassium hydroxide solution was dropped on the test piece, and the alkali resistance of the film was judged by measuring the time when the oxide film was dissolved. This method is not suitable for a film layer of 20 μm or more. Aluminium oxide thick films should be tested using the salt spray method.
A 10% potassium hydroxide solution was prepared using distilled water and then placed in a quantitative dropper for use. At least 3 test points are taken on the surface of the test piece. The size of each point is a circle with a diameter of 6 mm. Corrosion ink can be used to draw a circle. Then from 15 to 17 mg/s, the lye was dropped from the pipette to the detection point, dissolved into the oxide film, recorded the time (s), immediately placed in clean water and cleaned and dried, and then the surface resistance was measured with a resistance meter. Make sure that the membrane is completely dissolved. The test temperature should be kept at room temperature or a standard temperature (for example, 35°C). At this time, the test should be carried out in a special constant temperature tester capable of operating dripping lye to ensure constant temperature.
A 10% potassium hydroxide solution was prepared using distilled water and then placed in a quantitative dropper for use. At least 3 test points are taken on the surface of the test piece. The size of each point is a circle with a diameter of 6 mm. Corrosion ink can be used to draw a circle. Then from 15 to 17 mg/s, the lye was dropped from the pipette to the detection point, dissolved into the oxide film, recorded the time (s), immediately placed in clean water and cleaned and dried, and then the surface resistance was measured with a resistance meter. Make sure that the membrane is completely dissolved. The test temperature should be kept at room temperature or a standard temperature (for example, 35°C). At this time, the test should be carried out in a special constant temperature tester capable of operating dripping lye to ensure constant temperature.