33 Crucial Facts About Rust You Wish You Had Known Sooner

Rust is a common corrosion phenomenon that mostly takes place in iron and its alloys.

When iron metals are exposed to air or water for a long time, a layer of rust gets deposited on the surface. When rusting occurs, the metal becomes red or brown and eventually decays.

Rust is flaky, brittle, and fragile when dry but tacky, flexible, and tough when it is wet with water or alcohol. Thin films of rust are flammable.

It can also form on some materials that would not usually be expected to rust, such as concrete, stone, and plaster. Although rusting is generally a bad thing, it can protect underlying materials from further attack.

There are many questions about iron rust; what it is, why does iron rust, and how does any metal rust? Here are some facts to answer these questions.

Cause Of Rust

Rust is a process involving the oxidation and decaying of metal. Rust occurs because of a combination of moisture and oxygen, which causes the iron in the steel to corrode. Other factors such as temperature, humidity, and the presence of other materials can also influence the rate at which rust occurs.

Rust is a name given to the reddish-brown oxides and hydroxides of iron. It takes place when metals made of iron are exposed to oxygen and moisture for a long period of time.

The oxygen present in the air combines with metal forming new compounds which are collectively known as rust.

The reaction taking place is generally termed as an oxidation reaction as it involves the addition of oxygen.

Water or moisture present in the air serves as a catalyst for the reaction. The water molecules penetrate into the metal through pits and cracks.

The hydrogen atoms present in water combine with other elements to form its acids, which increases the exposure of metal to rust.

Types Of Rust

Rusts are of four types, depending on the color and type of reaction taking place. Rusting is the loss of electrons from the surface of metals due to chemical reactions with elements in their environment, such as oxygen or water vapor. There are two different types of rust: red/brown and black rust, apart from the other types mentioned.

Red rust: This type of rust is formed when the metal surface is exposed to high amounts of oxygen or water. The corrosion taking place is uniform corrosion wherein an even layer of oxidation appears across the surface of the material. Red rust is a corrosion product.

Yellow rust: This type of rust usually forms due to high exposure to moisture or water or metals that are found in large amounts of standing water.

Brown rust: This type of rust takes place when the supply of oxygen is more and the supply of moisture is less. They deposit on the surface non-uniformly, on specific areas of the material, and not on the entire surface.

Black rust: This type of rust forms when limited oxygen is applied or when oxygen cannot reach the metal and is trapped or covered by another metal. This type of rust is not very common and is not produced quickly.

Prevention

Iron and steel products are of wide use. Hence, it is important to protect them from rusting. There are many methods used for rust prevention.

Galvanization: This process involves protecting the metal using a layer of zinc by electroplating or hot-dip galvanizing. Zinc is preferred because it is cheap and provides cathodic protection to the metal.

Cathodic protection: This process involves supplying an electric charge to prevent corrosion and suppress the electrochemical reaction. It is achieved by attaching anodes in order to make the iron products, the cathode.

Paintings and coatings: Iron metals are coated with paints, varnishes, or wax tape to prevent the exposure of iron to the environment. A lot of modern equipment is applied with paints to prevent corrosion.

Treatment

Rust treatment is a topical compound designed to address the symptoms of rust. Rust treatment is the action of corrosion protection via anti-rust methods. Unlike rust prevention, which deals with measures to prevent or slow down the formation of rust, rust treatment deals with the removal and coating of rusty matter on surfaces where it is unwanted.

Rust can be removed from small objects by performing electrolysis using simple equipment used in the home, such as a plastic bucket, tap water, washing soda, or battery.

A length of rebar acts as an anode that is connected to the battery and an object to be protected serves as a cathode.

Rust can also be treated with a rust converter that contains tannic acid or phosphoric acid which combines with rust.

Organic acids like citric acid or vinegar are also a good option.

Other Miscellaneous Facts

Knowing a little bit about metals will help you understand this process better. For example, stainless steel does not rust easily. It is made from iron and chromium, but the main thing that makes it different is the fact that it has more chromium than iron in its makeup. This means it's easier to polish and clean but harder to oxidize! Making stainless steel a great material for creating things like refrigerators and ovens.

Rusting led to the collapse of the Mianus river bridge in 1983. The bearings rusted internally and destroyed one of the support slabs.

Rusting was an important factor in the silver bridge disaster of 1967 in West Virginia. In the incident, a steel bridge collapsed, killing 46 drivers and passengers.

Many industries in America have also experienced economic cutbacks, causing the region to be dubbed the 'rust belt'.

You have probably seen a metal object rust before, if not, it might be a surprise! Metals are a material made from Earth and the oxidization process is what creates rust.

The oxidation process of metals makes them look beat up by turning them into dirty orange or dark brown powdery substances called rust.

This may seem like a bad thing but the oxidation of metals is actually a very important process! It's an absolutely necessary part of everything from cars to space shuttles.

The rusting method starts as a thin layer that appears on the metal as it comes into contact with oxygen and water.

The outer layer that forms acts as a shield that protects the inner layers of metal from rusting.

Iron is one of the most common metals used to make cars and it is also one of the most well-known because it tends to start rusting almost immediately after its creation. But sometimes you will see an incredibly clean piece of iron, like a new knife or something at someone's house.

If the metal is covered in wax, oil, or paint, it cannot oxidize.

The process can still happen if the outer layer is scratched off but for an object to rust quickly and easily, it needs to be exposed to oxygen and water.

If the object is clean, it doesn't have any rust to protect it from returning to its original form. If there's no shield in place, then it'll just start oxidizing again.

The rust formation, described as hydrated iron oxide or Fe2O3·nH2O, is an electrochemical process; a chemical reaction that involves an electron transfer.

Two half-cells are created when different metals are used to make the metal surface exposed to oxygen and pure water available for oxidation. This results in rust formation.

Carbon dioxide (CO2) is created as surface rust forms. Red rust is the common name for the compound Fe(II)O(3), an oxide of iron, formed in the presence of water and free oxygen. It is usually found as an orange-red powder (the pigment red ochre) or a crust on iron or steel exposed to air and water.

Copper rust is a red-colored copper salt that forms as an oxide of the metal copper.

Using the right chemical process is completely different from using harmful chemicals for the cleaning process. This affects the structural integrity.

FAQs

What is rust made of?

Rust is a reddish-brown oxide of iron. It is formed when iron metals or alloys are exposed to oxygen and water for a long time.

How long does it take metal to rust?

Rusting can take place either slowly or within minutes depending on the condition of the environment, object, or heat. However, steel and iron-rich metals start developing rust after four to five days of exposure.

Can metal rust underwater?

Yes, metals can rust underwater since water has hydrogen and oxygen present in it.

Why is rust called rust?

The rusting process involves oxygen. The terms 'rust' and 'rusting' only mean oxidation of iron and its resulting product.

Do cars rust in the desert?

Cars can rust in the desert if they are exposed to water or moisture which act as a catalyst in the reaction.

Will rust spread if kept dry?

If one part of the object is exposed to water, oxygen, and electrolyte while the rest of the object is kept clean and dry, the rust on the wet part will not spread to the dry part.

How can rust be prevented?

Rust can be prevented by protecting the object using a layer of zinc or through electrolysis, or by painting the metal surface with paints and varnishes.

Why does rust turn red?

When the metal is exposed to a high supply of water and oxygen, the rust turns red.

What is blue rust?

Blue rust is formed when steel is partially protected against rust using a black oxide coating. It is named because of its blue-black appearance.