Test of coating resistance to high temperature air oxidation

       The oxidation resistance of the coating itself was first determined. On the flat substrate sample, spray salt water first and then carry out the spraying procedure. After the sample is made, place it in water to separate the coating from the substrate. After cleaning and weighing, put it into a heating furnace, keep it at the test temperature for 1h~2h, take the sample out of the furnace, cool it at room temperature and weigh it. Repeat the test to obtain the change curve of the oxidation weight gain of the sample with time, which can indicate the oxidation resistance of the coating. It can be combined with metallographic or scanning electron microscope to analyze the oxidation of the coating to evaluate and study the anti-oxidation performance of the coating.



Next, the protective performance of the coating against the high temperature oxidation of the substrate was determined. This test is to expose the coating sample to high temperature air, and measure the effect of exposure time on the weight to directly express the oxidation resistance of the coating. The test method is generally to spray a coating of an appropriate thickness on an ordinary steel rod of φ6.5 x 100mm according to the regular procedure, and then weigh it (accurate to 10mg). The sample is placed in an air oven with a set temperature of 1000°C or 1300°C and heated, and kept warm. Regularly observe the surface state of the sample, if the coating is damaged, record the result and the test is over. If the coating is intact after 24 hours, the sample is taken out of the furnace and cooled to room temperature naturally in the atmosphere. If the coating is still intact after cooling, repeat the above test after weighing the sample. Ideally, the coating is still intact after several weeks of repetition. After the predetermined test time, the sample can be cut to check the oxidation of the substrate and evaluate the protective effect of the coating on the substrate.