Galvanization is a process used to prevent the rusting of iron. When iron is exposed to moisture and oxygen, it undergoes a chemical reaction called oxidation, which results in the formation of iron oxide, commonly known as rust. Rusting weakens the iron and eventually leads to its degradation.

Galvanization involves coating iron or steel with a layer of zinc to protect it from rusting. Zinc is highly resistant to corrosion and acts as a sacrificial anode, meaning it corrodes in place of the iron. This sacrificial protection helps to preserve the structural integrity of the iron or steel.

The process of galvanization typically involves the following steps:

1. Surface Preparation: The iron or steel surface is cleaned to remove any dirt, grease, or oxide layers. This can be done through various methods such as degreasing, acid pickling, or abrasive cleaning.

2. Fluxing: The cleaned surface is then treated with a flux, which helps to remove any remaining oxide layers and promotes the adhesion of the zinc coating. Common fluxes used in galvanization include ammonium chloride or zinc chloride solutions.

3. Immersion in a Zinc Bath: The iron or steel object is immersed in a bath of molten zinc, typically at a temperature of around 450°C (842°F). The zinc coating is applied through a process called hot-dip galvanization, where the object is completely submerged in the zinc bath.

4. Formation of Zinc Layers: As the object is withdrawn from the zinc bath, the molten zinc adheres to its surface. The zinc reacts with the iron or steel to form a series of zinc-iron intermetallic layers, providing a strong and durable coating.

5. Finishing: The galvanized object is cooled and then subjected to various finishing processes, such as quenching, passivation, or chromating, to improve its appearance, durability, and resistance to corrosion.

By applying a layer of zinc through galvanization, the iron or steel object is effectively protected from rusting. The zinc coating acts as a physical barrier, preventing moisture and oxygen from reaching the underlying metal. Additionally, even if the zinc coating is damaged or scratched, the zinc sacrificially corrodes instead of the iron, providing ongoing protection.

In conclusion, galvanization is a process used to prevent the rusting of iron by coating it with a layer of zinc. This process helps to protect iron and steel objects from corrosion, extending their lifespan and maintaining their structural integrity.