Railway tracks form the backbone of land transportation across the world. Despite being constantly exposed to rain, moisture, weather, and heavy use, the steel rails on which trains run rarely show significant rusting. While most iron or steel objects develop rust quickly when exposed to the elements, railway tracks remain comparatively rust-free for decades — and scientists have discovered the fascinating reasons behind this.
What Railway Tracks Are Made Of
Railway tracks are not made of ordinary iron. Instead, they are manufactured from high-grade alloy steel with a carefully balanced composition of carbon and manganese. This type of steel is much stronger and more resistant to wear, tear, and chemical reactions that lead to corrosion.
Engineers design these rails to handle extreme loads — including heavy cargo trains and high-speed passenger trains — across diverse geographical conditions, from deserts to mountains. The steel used is typically hot-rolled and weighs 52 kg or 60 kg per meter, making it durable enough to withstand heavy usage and weathering.
Why Rust Usually Occurs
Rust is an oxidation reaction that happens when iron reacts with oxygen and water. In ordinary steel or iron objects such as tools, garden equipment, or exposed metal surfaces, moisture and oxygen combine to form iron oxide, commonly known as rust. Left untreated, rust weakens metal, compromises strength, and can lead to structural failure.
Why Railway Tracks Don’t Rust Easily
There are multiple reasons why rails are resistant to significant rust:
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High-quality steel alloy: The specific blend of carbon and manganese slows down the oxidation process, making these rails much less prone to rust compared to ordinary iron.
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Surface friction from trains: The constant pressure and movement of train wheels naturally polish the surface, removing any light surface oxidation before it can deepen into rust.
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Mechanical grinding and maintenance: Railways often grind tracks during maintenance, which removes initial rust or surface impurities, preventing long-term corrosion.
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Protective coatings (in some regions): In highly corrosive environments, like coastal areas, railway authorities may use galvanized steel or corrosion-resistant treatments to further protect tracks.
Role of Train Traffic
The frequent passage of trains over tracks plays an important role in inhibiting rust. As wheels roll over the rails, they scrape and rub against the surface, removing moisture and any minimal oxidization that may begin. This constant friction acts like a natural polishing mechanism, keeping the top surface smooth and shiny.
Environmental Factors
While rain, humidity, and harsh weather conditions tend to accelerate rust in metals, the quality of the steel, frequent traffic, and regular maintenance collectively reduce the likelihood of corrosion. However, rust can still form in unused sections of track or in areas where trains rarely pass.
