Paint is applied to iron articles for several important reasons:

1. Corrosion Prevention: One of the primary reasons for painting iron articles is to protect them from corrosion. Iron and steel are prone to rust when exposed to moisture and oxygen in the air. The paint forms a protective barrier, preventing direct contact between the iron surface and the external environment. This helps to inhibit the oxidation of iron and the formation of rust.

2. Enhanced Durability: Painting iron articles can significantly extend their lifespan by preventing or slowing down the degradation caused by rust and other environmental factors. A well-applied paint coating can provide long-term protection, reducing the need for frequent replacement or maintenance.

3. Aesthetic Appeal: Painting iron articles also serves aesthetic purposes. It can improve the appearance of iron structures and objects, making them more visually appealing. The choice of color and finish can be customized to match the desired aesthetic or architectural style.

4. Easy Maintenance: Painted surfaces are generally easier to clean and maintain compared to untreated iron. Cleaning and repainting, when necessary, can help keep the iron articles looking fresh and well-preserved.

5. Environmental Protection: By preventing rust and corrosion, painting iron articles can contribute to environmental protection and sustainability. Extending the life of iron objects reduces the need for new manufacturing, which in turn conserves resources and reduces energy consumption.

6. Structural Integrity: In the case of iron structural elements, such as bridges and buildings, painting can help maintain the structural integrity of these objects. Rust can weaken the metal and compromise its load-bearing capacity, so preventing rust through painting is essential for safety.

7. Easy Identification: Painting can also be used to mark or label iron articles, making them easily identifiable for various purposes, such as labeling pipes in an industrial setting.

In summary, applying paint on iron articles primarily serves to protect the metal from corrosion, enhance durability, and improve the appearance of the objects. It is an effective and widely used method for preserving and maintaining iron structures and items.