Tarnijasuhteid

Tarnijasuhteid, also known as tarnish, is a term used in the field of metallurgy to describe the discoloration or degradation of a metal's surface due to chemical reactions with its environment. This process typically occurs over time and can result in a loss of the metal's aesthetic appeal and protective properties. Tarnish is commonly observed on silver, copper, and other metals that are susceptible to oxidation.

The formation of tarnish involves the reaction of the metal with oxygen, sulfur, or other environmental contaminants. For instance, silver tarnishes when it reacts with hydrogen sulfide present in the air, forming silver sulfide (Ag2S), which appears as a black or gray film. Similarly, copper tarnishes when it reacts with oxygen and moisture, forming copper oxide (CuO or Cu2O), which can appear as a green or blue patina.

Tarnish can be prevented or removed through various methods. Preventive measures include storing metals in controlled environments, using protective coatings, or applying chemical treatments. Removal techniques may involve mechanical polishing, chemical cleaning, or electroplating to restore the metal's original appearance and properties.

Tarnish is not to be confused with corrosion, although both processes involve the degradation of a metal's surface. Corrosion typically refers to the deterioration of a metal due to chemical reactions with its environment, often resulting in the formation of oxides, sulfides, or other compounds. While tarnish can contribute to corrosion, it is often used more specifically to describe the discoloration of metals that are not necessarily undergoing significant structural damage.