Definition - What does Cadmium mean?
Cadmium refers to a metallic chemical substance with the symbol Cd and an atomic number of 48. Cadmium is silver-white in appearance and has strong corrosion resistance properties.
Corrosionpedia explains Cadmium
Cadmium is widely used in industrial applications as a plating material on metallic substrates to prevent or reduce corrosion. The mechanism of electrodeposition from a sulfate electrolyte is the primary means by which cadmium is applied to such surfaces.
In the case of iron, cadmium is anodic and can resist moisture rich atmospheres better than zinc can. Alternatively, cadmium plating is done in cyanide baths containing a mixture of cadmium oxide and sodium cyanide to produce Na2Cd(CN)4.
Cadmium can be used in a wide range of atmospheres. In a typical industrial atmosphere, a 25 µm thick coating has the potential to last for one year. However, in a marine environment, that lifespan is significantly increased. In saline environments, the chloride and insoluble carbonates are produced and not washed out from the surface. They provide good protection for steel and other metals in stagnant, acidic or alkaline conditions.
Some properties of cadmium:
- Atomic number: 48
- Atomic weight: 112.41
- Specific gravity: 8.65
- Melting point: 321.1°C (609.9°F)
- Boiling point 767°C (1,413°F)
- Valence: 2