Metal alloy coating
Metal and alloy coatings are increasingly favored as the modern ship industry puts forward higher requirements for temperature, pressure and so on.
At present, the most widely used alloy coating is cobalt-nickel cesium alloy coating, which not only has the fine characteristics of metal and its alloy but also has the characteristics of the controllable composition, the stable property of the material itself and very stable contact interface of the coating. It can form stable oxides at high temperatures, such as alumina, which is beneficial to the corrosion protection of protected materials. The composition of the material itself is easy to adjust and can be adjusted according to different requirements to improve the performance of the coating.
Ceramic coatings have many excellent characteristics, such as high hardness, high chemical stability, and high corrosion resistance and so on. Ceramic coating is free from the restriction on the study of the matrix and can be studied as an individual without affecting its performance. Besides that, the ceramic coating is not limited by the size of the matrix, and it is easy to be effectively repaired after the ceramic is damaged. However, ceramic materials also have their disadvantages, such as less toughness than metal materials, and it is easy to peel off with ship deformation or collision after coating the matrix.
Cermet composite coating
Ordinary metal alloy coating on the surface of ships is easy to cause friction, potential corrosion, corrosion of seawater and other circumstances resulting in the coating fall off, thus losing the role of the coating. The cermet composite coating not only has the toughness of metal but also has the chemical inertness of ceramic itself, which can effectively block the corrosion caused by seawater and potential.
There are many factors influencing corrosion resistance of the cermet, such as coating layer number, coating composition, coating thickness and spraying technology. The performance of the matrix material itself should be taken into account when considering coating, and it is the key to obtain the optimal important parameter ratio, which is also an important direction to explore the development of metal ceramic materials. The coating technology of cermet coating is also an important factor affecting its corrosion resistance, and finding more suitable coating technology will be the key to future research.
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