How does zinc contribute to the steel industry
Zinc is found in Earth’s crust in abundance and comes with an array of uses. It is widely used for industrial and biological purposes. Zinc is blue-white in appearance at the room temperature and is the fourth most widely consumed metal. Zinc is used for various purposes. However, 50 percent of it is applied in corrosion protection of steel and iron.
Zinc is a blessing for steel. Without it, all the steel buildings and bridges are at risk of getting corroded away and collapsing. However, thin layers of zinc are added to the steel to prevent rusting and protect it. The process is called zinc galvanizing.
The reason zinc is used out of all the material is that it won’t oxidize when exposed to water and air. Moreover, it becomes a strong barrier between the corrosive environment and steel. It prevents the steel from getting corroded by keeping the moisture away from the steel. Moreover, it provides sacrificial cathodic protection and losses itself first if there’s any scratch exposing the steel to moisture.
The most common process to galvanize steel is called Hot-dip galvanizing. The process requires the steel to be immersed in molten zinc to produce a uniform layer coating. A metallurgical reaction takes place between the molten zinc and the iron in the steel, causing a uniform coating through-out the surface. After it cools down, the steel and zinc form a solid bond that has the ability to last for up to 50-years in normal conditions and with very little maintenance.
The steel galvanized zinc has various applications:
- Protecting underwater structures: Due to its properties, zinc will corrode first and provide cathodic protection to steel. Thus, it is quite beneficial for structures that are underwater like a ship’s hull, pipelines, bridges, and drilling equipment. If there’s an uncoated area on the steel surface, the surrounding zinc will sacrifice itself to protect steel.
- Automotive: There are numerous parts of car structures composed of steel that are susceptible to corrosion. For these parts, steel galvanized with zinc is used. The zinc coating is very seamless and there is no visible difference in appearance after coating the surface. This coating protects the vehicle’s structure to a large extent from getting corroded and damaged.
- Buildings and construction purposes: This industry makes use of two-third of the zinc-coated steel. The zinc-coated steel is applied in roofing and cladding of buildings. Thus, it protects the buildings well from corrosion.