What is the Difference Between Iron and Steel?

Iron and steel are two of the most important materials used in the manufacturing industry. They are used in everything from construction to transportation, and without them, modern society would be vastly different. 

Iron and steel stand as the backbone of modern civilization, indispensable in various sectors, from construction to transportation. Their versatility and durability have propelled industries forward, shaping the infrastructure and machinery that define our daily lives. Their significance extends far beyond mere materials, embodying the progress of human ingenuity and innovation.

But what exactly is the difference between iron and steel? Which is stronger, iron or steel, and why? In this blog post, we will explore the answers to these questions and more.

What is Iron?

Iron is a chemical element with the symbol Fe (from Latin: ferrum) and atomic number 26. It is a metal that is commonly found in the Earth’s crust and is the fourth most abundant element in the universe. Iron is known for its strength and ductility, making it an important material in construction and engineering.

Iron Composition

• Pig iron is the initial product of smelting iron ore with coke or charcoal and is high in carbon content.
• It's typically further refined to produce steel or cast iron products.
• Its name comes from the resemblance of the molds used to transport it to piglets suckling on a sow.

Pure iron is a relatively soft metal and is not commonly used in its pure form. Instead, it is typically combined with other elements to form alloys, which are stronger and more durable than pure iron. Iron composition can be divided into two main categories: wrought iron and cast iron.

• Wrought iron is an alloy of iron with a very low carbon content, typically less than 0.08%. It is known for its toughness and ductility and was commonly used in the construction of buildings and bridges in the 19th century. Today, wrought iron is not commonly used, as it has been largely replaced by steel.
• Cast iron is an alloy of iron with a higher carbon content, typically between 2.1% and 4%. It is known for its hardness and brittleness and is used in the manufacturing of things like engine blocks, pipes, and cookware.

Uses of Iron

Iron is used in a wide range of applications, from construction to transportation to manufacturing. Iron finds its way into numerous applications, from structural supports in buildings to components in machinery. Its magnetic properties also make it essential in electrical equipment and technology. Some common uses of iron include:

• Construction: Iron is used in the construction of buildings, bridges, and other structures because of its strength and durability.
• Automobile: Iron is used in the manufacturing of cars, trains, and other vehicles because of its strength and resistance to corrosion.
• Manufacturing: Iron is used in the manufacturing of machinery and equipment because of its strength and durability.
• Everyday items: Iron is used in the manufacturing of everyday items like cutlery, nails, and screws.

Also Read: Types of Iron Ore in India and Its Production

Alloy of Iron

An alloy of iron, known for its versatility, strength, and resilience, forms the backbone of numerous industrial applications. Steel, the most prevalent alloy, combines iron with carbon and other elements like chromium, nickel, or manganese to enhance its properties. From construction to automotive manufacturing, this alloy's adaptability and durability make it indispensable. Its composition can be fine-tuned to suit specific needs, ensuring it remains a cornerstone of modern engineering and infrastructure.

What is Steel?

Steel is an alloy of iron and carbon, with carbon content typically between 0.2% and 2.1%. It is a much stronger and more durable material than iron and is commonly used in construction, manufacturing, and other industries.

Steel Composition

The carbon content of steel is what gives it its strength and durability. When carbon is added to iron, it forms a new material with unique properties. The more carbon that is added, the stronger and harder the steel becomes.

There are many different types of steel alloys, each with its own unique properties and uses. Some common types of steel alloys include:

• Carbon steel: This is the most common type of steel, and is used in everything from construction to manufacturing. It is made by combining iron with carbon, and has a carbon content of up to 2.1%.
• Stainless steel: This is a type of steel that is resistant to corrosion and staining. It is made by adding chromium to the steel, which forms a protective layer on the surface of the metal.
• Tool steel: This is a type of steel that is designed for use in cutting and shaping other materials. It is made by adding tungsten, molybdenum, or other elements to the steel.

Also Read: Stainless Steel vs Carbon Steel: Understanding the Fundamental Differences!

Uses of Steel

Steel is used in a wide range of applications, from construction to manufacturing to transportation. Steel is a versatile material used in construction, automotive manufacturing, and household appliances. Its strength and durability make it ideal for bridges, skyscrapers, and even cutlery. Some common uses of steel include:

• Construction: Steel is used in the construction of buildings, bridges, and other structures because of its strength and durability.
• Manufacturing: Steel is used in the manufacturing of machinery and equipment because of its strength and durability.
• Transportation: Steel is used in the manufacturing of cars, ships, and airplanes because of its strength and resistance to corrosion.
• Everyday items: Steel is used in the manufacturing of everyday items like cutlery, appliances, and furniture.

Alloy Steel

An alloy of steel is a combination of iron with other elements, typically carbon, to enhance its properties. Alloying elements like chromium, nickel, and manganese are added to alter characteristics such as strength, hardness, and corrosion resistance. Through precise composition adjustments, alloyed steel can be tailored for specific applications, from structural components in buildings to high-performance tools and machinery parts. This versatility makes alloyed steel indispensable across industries like construction, automotive, and aerospace.

Difference Between Iron and Steel

Now that we understand what iron and steel are, let’s dive into the difference between iron and steel.

1. Strength and Durability

While iron is a strong and durable material, it is not as strong as steel. Steel is an alloy of iron and carbon, which gives it greater strength and durability than iron. This is why steel is used in applications where high strength and durability are required.

2. Composition

As we discussed earlier, iron is typically combined with other elements to form alloys. Cast iron, for example, has a higher carbon content than wrought iron, which makes it harder and more brittle. Steel, on the other hand, is an alloy of iron and carbon with a specific carbon content that gives it its unique properties.

3. Uses

While both iron and steel are used in a wide range of applications, they are often used for different purposes. Iron is commonly used in construction, transportation, and manufacturing, while steel is used in applications where higher strength and durability are required, such as building construction, machinery, and transportation.

4. Corrosion

Iron is highly prone to corrosion when exposed to moisture and oxygen, forming rust, which weakens its structural integrity over time. On the contrary, steel, especially stainless steel, contains additional elements like chromium, which forms a protective oxide layer, delaying corrosion significantly. This makes steel more resistant to rust and corrosion in various environments, making it suitable for outdoor applications and harsh conditions.

5. Versatility

Iron has limited versatility compared to steel. While iron is primarily used in construction and manufacturing, steel offers a wide range of applications due to its diverse properties. Steel can be alloyed with other metals to enhance its strength, flexibility, and corrosion resistance, making it suitable for construction, automotive, aerospace, and even household appliances. Its versatility makes steel a preferred choice in many industries.

6. Sustainability

In terms of sustainability, both iron and steel have their challenges. Iron extraction from ores involves significant energy consumption and environmental impact, contributing to carbon emissions and habitat destruction. However, steel is often recycled, reducing the need for virgin iron ore and energy-intensive production processes. Recycled steel also requires less energy and emits fewer greenhouse gases, making it a more sustainable option compared to iron in many cases.

7. Cost

Cost-wise, iron is generally cheaper than steel due to its simpler production process and abundance. However, the final cost of steel depends on factors such as alloying elements, manufacturing methods, and market demand. While basic carbon steel may be cost-effective, specialty steels with added alloys can be significantly more expensive. Additionally, the longevity and durability of steel often justify its higher initial cost compared to iron, making it a more cost-effective choice in the long run for many applications.

Which is Stronger Iron or Steel?

When it comes to strength and durability, steel is the clear winner. This is because steel is an alloy of iron and carbon, which gives it greater strength and durability than iron. Steel is also more resistant to corrosion and wear than iron, which makes it a better choice for applications where long-term durability is important.

Wrapping It Up

In a nutshell, iron and steel are two of the most important materials in the manufacturing industry. While both materials have their unique properties and uses, steel is generally considered to be stronger and more durable than iron. 

Whether you’re building a bridge, manufacturing a car, or simply using everyday items like cutlery, understanding the difference between iron and steel can help you make more informed decisions about the materials you choose to use.

Read More: Various Benefits & Advantages of Steel in Our Lives