Method for evaluating service life of organic coating in seawater total immersion environment

Abstract

The invention provides a method for evaluating the service life of an organic coating in a seawater total immersion environment by considering the influence of temperature and chloride ions. The method comprises the following implementation steps: 1, establishing an aging model of the organic anticorrosive coating; 2, establishing an environment profile of the coating structure in the service period; 3, fitting a distribution function of a reaction constant theta; 4, determining a coating electrochemical parameter failure threshold according to the natural environment data; and 5, evaluating the reliability of the organic coating by using a stress-strength interference theory. Through the above steps, a coating accelerated aging test and environmental factor correlation model is integrally established for a qualitative logic relation and a quantitative model method for organic coating reliability assessment; the definition of the service life and the reliability of the organic coating is realized, so that the failure criterion of the organic coating system is more timely, accurate and reasonable; according to the invention, the measurement parameters of the coating structure are electrochemical parameters, the test method is simple, the operation is convenient, and the structure is not damaged.

Description

technical field [0001] The invention provides a method for evaluating the life of an organic coating in a seawater immersion environment, that is, a method for evaluating the life of an organic coating in a seawater immersion environment considering the influence of temperature and chloride ions. It relates to an organic coating based on polyurethane. A time-varying life evaluation method for anti-corrosion coatings in seawater immersion environments, which is based on electrochemical tests, stress-strength interference theory and organic [0002] The organic anti-corrosion coating life evaluation method based on the coating aging kinetic model, which comprehensively establishes the accelerated test for the accelerated aging test data of the coating in the organic anti-corrosion coating system, the corrosion current change data of the base metal under the coating, and the corrosion environment factors The correlation model between coating degradation and environmental factors ...

AI Technical Summary

Problems solved by technology

[0004] Existing evaluation tests for the aging state of organic anti-corrosion coatings usually only include loss of light rate, degree of discoloration, degree of differentiation and cracking, density of bubbles, and peeling area, which cannot evaluate the anti-corrosion performance of organic anti-corrosion coatings in a timely and accurate manner. lower

The study found that the decline in the anticorrosion performance of organic anticorrosion coatings is due to the change in the penetration of water molecules and ions inside the coating, which causes partial or overall degradation of the electrochemical properties of the coating and the ability to isolate the corrosive environment, resulting in a decline in the anticorrosion performance of the coating.

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