Research On Electrochemical Corrosion Behavior Of Nickel-Based Alloys In Service In Marine Environment

The development of marine economy and marine technology has been elevated to unprecedented strategic heights in China.Strategic emerging marine industries such as coastal engineering,marine mining,and underwater engineering are rapidly emerging.The development and construction of various new types of high-level deep-sea drilling equipment,ships,facilities such as submersibles and marine space stations are the fundamental material guarantee for the development of marine resources and the maintenance of national defense security.However,the harsh environment of the marine atmosphere has undoubtedly brought a huge threat to the corrosion of ships and even marine gas turbines.Corrosion is different from other engineering accidents.It is always carried out quietly.It is very concealed and difficult to monitor in real time.In order to improve the reliability and service life of equipment and reduce the amount of materials used,the science of corrosion and protection is widely valued by countries.Countries around the world are paying attention to the development of anti-corrosion technology and anti-corrosive materials in order to effectively control corrosion.Research on the use of high-performance corrosion-resistant materials can slow down corrosion products and prevent material leakage caused by corrosion damage,which also plays an important role in the development of environmental technology.This paper takes the corrosion of nickel-based alloys as the research topic,and the main contents include the following four aspects:(1)First,according to the marine atmospheric environment in which marine gas turbine and coastal aircraft engine blades are located,the development history and application research status of the gas turbine manufacturing material nickel-based alloy are introduced,and the corrosion characteristics,corrosion environment and mechanism of the material are analyzed;(2)Secondly,comparatively study the electrochemical corrosion behavior of CMSX-4 and RenéN5 alloy in 3.5 wt.%Na Cl solution(artificial seawater),and discuss the difference of corrosion behavior of CMSX-4 and RenéN5 nickel-based alloys in marine atmospheric environment;(3)The corrosion mechanism of CMSX-4 alloy in the marine environment is studied in particular,and a longer passivation interval is found in the polarization curve,thereby supporting its strong corrosion resistance;(4)Finally,a certain amount of ZrO₂nanoparticles was added to the configured plating solution,and a Ni-ZrO₂nano-coating was prepared on the surface of a cobalt-nickel-based model alloy sample by means of magnetic stirring assisted electrodeposition.Based on orthogonal experiments,the electrochemical free corrosion current density of Ni-ZrO₂nano-coating was used to predict its corrosion rate.Through the close combination of neural network and electrochemical method research,experiments have proved that it can provide a new idea and new method for research in this field.