| The metal material is the important foundation of our national engineering and defense construction. The research of evaluating the corrosion of metal materials in the atmospheric environment accurately and quickly, accelerating corrosion test and the correlation on the test inside and outside are the main subjects in the corrosion &prevention field.The corrosion of materials in the marine atmosphere is an important part of this paper on atmospheric corrosion. This paper focuses on the study of the corrosion about the harsh marine environment in the East island of Zhanjiang. Three kinds of different corrosion rates' material which is carbon steel Q235, copper and stainless steel 304 are selected to test under the blazing sun for quite a long time, with addition of collecting and analyzing date of environmental corrosion. After the period, the analysis of the corrosion behavior and corrosion mechanism on the composition and structure of the rust layer are conducted by studying erosion thickness, the morphology record of the corroded rust layer corrosion process used by a digital camera, posture microscope and scanning electron microscope,XRD and EDS. Based on the metal corrosion behavior, corrosion mechanism and the design principle of the week immersion corrosion device, the accelerated corrosion of real sea device and the related tests are completed. For simulating the actual marine atmospheric environment, two kinds of accelerated corrosion sampling tests of the accelerated corrosion and salt spray tests are carried out to search for their correlations.The main conclusions are as follows:1?The corrosion rate of Q235, Cu and 304 in the marine atmospheric environment is basically in a stable state. The corrosive of Q235 is bad while the corrosion rate of Q235 is high. With the corrosion time extended, the substrate surface will cover with a relatively thick rust layer. However, copper shows a good corrosive but a lower corrosion rate. And the substrate surface is evenly covered with thin rust layer. But 304 is only localized pitting.2?The accelerated corrosion tests of real sea simulate the dry and wet cyclic processof material corrosion under marine atmospheric environment. In accelerating corrosion test for 90 days, the characteristics of high temperature, high humidity, high rainfall and high sunshine are perfectly revealed through natural exposure in the process.3?The corrosion of a liquid film can be formed on the surface of the sample in the salt spray test. Corrosion morphology of samples and natural exposure test are poor without drying process. Besides, the corrosion rate of copper and Q235 in salt spray test condition is 2 and 5 times of the corrosion rate in natural exposure condition. As a result, the acceleration quality and the correlation are poor.4?The formatting corrosion layer of Q235 and Cu in accelerating corrosion test is similar to the natural exposure. The macro and microstructure morphology, Q235 rust layer is in agreement with the natural exposure test of porous and poor adhesive. The composition of Q235 is the same as the natural exposure, including Fe2O3. Fe2O4,?, ?,?-Fe OOH. The results of Q235 and copper corrosion kinetics curves which are in line with the power function model D=Atn are in agreement with those of natural exposure as a result of good simulation. The corrosion rate of Q235 and copper in the accelerated corrosion test is 10 and 12 times of the corrosion rate in the natural exposure test, with efficient acceleration. Therefore, the real sea accelerated corrosion and natural exposure tests have both acquired good correlation.In this paper, one innovation was made to complete the new pattern of accelerating device — real sea accelerated corrosion device. When the real sea accelerated corrosion test was completed with real sea accelerated corrosion device placed under the real sea atmospheric environment, the result had a better correlation with that acquired from the exposure test under marine atmospheric environment. |
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