Introduction
Corrosion is an irreversible event, which can significantly reduce the lifetime and reliability of composite materials. It is widely acknowledged that developing effective strategies to enhance the corrosion resistance of composite materials can significantly expand the scope of their use. Corrosion resistance of composite materials is the ability of a material to resist the destructive effects of the environment (such as air, moisture, acids, alkalis, etc.). The corrosion resistance of a composite material is determined by its microstructure, the chemical composition of the base material and the type of coating used.
Definition of corrosion resistance
Corrosion resistance is the ability of composite materials of a material to resist chemical or electrochemical reactions with its environment. The corrosion resistance of composite materials is often compared to its corrosion resistance with different environments in terms of weight loss, corrosion rate, and corrosion potential. Depending on the characteristics of the composite material, corrosion resistance can be divided into general and localized. General corrosion resistance refers to uniform corrosion while localized corrosion resistance is the resistance towards a local area of metal’s surface.
Analysis of corrosion resistance
The corrosion resistance of composite materials is usually studied by several methods, such as corrosion testing in saline solution (for individual components), accelerated corrosion tests and electrochemical tests. Each method yields different information about the materials resistance against different forms of corrosion.
1. Corrosion testing in saline solution
Corrosion testing in saline solutions involves immersing the composite material in a saline solution and then examining the progression of deterioration. The degree of corrosion resistance is typically determined by the amount of weight loss. This method is suitable for cases where the material to be tested has sufficient ductility.
2. Accelerated corrosion tests
Accelerated corrosion tests are carried out to simulate the corrosive environment of the composite material. This is done by placing the composite material in a chamber and artificially accelerating the corrosion reaction. The degree of corrosion resistance is generally determined by the amount of visual and/or microscopic damage to the material after test.
3. Electrochemical tests
Electrochemical tests are used to study the relative corrosion resistance of different materials exposed to the same corrosive environment. The corrosion rate is then calculated by measuring the corrosion potential and the current flowing through the material.
Conclusion
In conclusion, corrosion resistance is the ability of a material to resist chemical or electrochemical reactions with its environment. The corrosion resistance of composite materials can be evaluated by several methods such as corrosion testing in saline solution, accelerated corrosion tests and electrochemical tests. These methods will assess the materials relative corrosion resistance, determine the corrosive environment of the material, and calculate the corrosion rate. Understanding the correlation between the environment, the material and the corrosion rate is critical for developing effective strategies to enhance the corrosion resistance of composite materials.
