Passzívréteg

Passzívréteg, often translated as passive layer or passivation layer, refers to a protective film that forms on the surface of certain metals and alloys. This layer is typically thin, often only a few nanometers thick, and is formed by a chemical reaction between the metal and its environment. The most common way this layer forms is through oxidation, where the metal reacts with oxygen in the air or in an electrolyte.

The primary function of a passzívréteg is to prevent further corrosion or degradation of the underlying material. It acts as a barrier, preventing corrosive agents such as water, acids, or salts from reaching the metal surface and initiating electrochemical reactions that lead to rust or other forms of decay. The effectiveness of the passzívréteg depends on its composition, thickness, and adherence to the substrate.

Common examples of metals that readily form passzívréteg include aluminum, chromium, titanium, and stainless steel. Aluminum forms a tenacious aluminum oxide layer that protects it from atmospheric corrosion. Stainless steel owes its corrosion resistance to a chromium oxide layer that is continuously reformed if the surface is scratched.

The formation and maintenance of a passzívréteg can be influenced by environmental conditions, such as pH, temperature, and the presence of specific chemical species. In some cases, artificial passivation treatments are employed to enhance the protective properties of this layer. Understanding and controlling the formation of passzívréteg is crucial in various industries, including aerospace, automotive, and chemical processing, to ensure the longevity and reliability of metallic components.