Whether you are engaged in the construction or manufacturing sector or looking to buy cooking ware for your kitchen utensils, it’s a smart move to understand the difference between iron and cast iron and other popular materials such as steel.

Iron is a pure element, and is soft, malleable and often used as a raw material for others. Its alloys, namely steel and cast iron, are more functional.

Cast iron, with high carbon content is hard and often used for making kitchenware such as pots and pans. Steel, with parts chromium, nickel and other metals is versatile, making it suitable for construction materials, tools and vehicles.

But what are the benefits of cast iron over steel? Or, what are the disadvantages of cast iron? How to decide which is better – iron vs cast iron vs steel? We answer such queries and more in this blog today.

Difference between iron and cast iron

When choosing materials for different applications it’s important to know about their properties and characteristics that make them suitable for use. In the table below, we list the main differences between iron and cast iron. We also compare it to steel to illustrate the difference between iron’s popular alloys.

Iron vs Cast iron vs Steel – Main differences

Selecting the right material is important for optimal performance and longevity. It will also impact cost-effectiveness and efficiency of projects across sectors.

What is cast iron?

Now that we have looked at the difference between iron vs cast iron vs steel, let’s take a closer look at cast iron in specific.

Cast iron is a strong and durable alloy made out of iron and parts carbon (usually 2% – 4%), and silicon.

It is manufactured by melting pig iron, steel scrap and iron alloys. The molten iron is then poured into casts or molds of different shapes based on its final use.

Cast iron is rigid, resistant to wear, and can deform under compression. It is however brittle and can break under high stress. It also has high heat retention properties. It is used extensively in making pipes, automotive components, and cookware.

Must read: Grey Cast Iron: Definition, Composition, Manufacturing Process, and Applications

It is also affordable and recyclable, making it a staple across urban and rural settings.

Is there a difference between iron and cast iron?

As can be seen, there are some basic differences between iron and cast iron which makes it suitable to use the specific metals for specific applications.

• General properties: Iron, as a pure metal, is soft, ductile and malleable. Because it’s soft for use in everyday applications, it is alloyed with other metals to make steel and cast iron which are stronger and more durable.
• Heat resistant: Cast iron, due to its high carbon content (2% – 4%) is harder and more wear-resistant than iron. It is heat resistant and can distribute it evenly making it suitable for manufacturing pots, pans and similar items. It’s also more durable than iron.
• Brittleness: Cast iron however is brittle and will break under stress. Iron on the other hand is highly ductile and can be hammed at room temperature.
• Melting point: Cast iron has lower melting point than iron and can be cast and mold into different shapes with ease.

Advantages and disadvantages of cast iron

Before we take a look at the benefits of cast iron and the problems of cast iron, let’s have a look at the main pros and cons.

Advantages and disadvantages of cast iron:

What are the disadvantages of cast iron?

From the table above, it is obvious that case iron has some disadvantages , especially when compared to iron and steel. Understanding these drawbacks are essentials for consumers and manufacturers to enable them make informed business decisions.

Disadvantages of cast iron – In industrial and culinary applications

• Heavy and inconvenient: Cast iron is heavier than iron and steel. This makes its transportation challenging as attention has to be paid to packaging and materials handling. Moreover, due to its heaviness, it is also used in a limited way with preference being given to lighter materials (e.g., stainless steel).
• Corrosion prone: Cast iron is prone to corrosion unless treated properly. This often makes steel a more preferred metal. Different steel alloys come with distinct properties and coatings, that make it corrosion and rust resistant and suitable for use across a myriad of applications.
• Limited workability: When compared to iron, cast iron has lower workability. Put simply, this means that iron can be hammed and shaped and worked with even at room temperatures.
• Higher melting point: Cast iron has a melting point of approximately 1150° -1300°C. This means that more energy is required for melting and subsequent casting. Iron on the other hand melts at lower temperatures and is less energy-intensive.
• Lower brittleness: Cast iron is less shock-resistant and brittle when compared to iron and steel which are more ductile. This means that if there’s sudden impact, cast iron will crack or break.

What is main problem you will find with cast iron?

We’ve looked at the main disadvantages of cast iron, so here’s the question – what is the main problem when using cast iron?

This has to be in context of its application. For instance, with a cast iron cookware like pots or pans, the main problem is its low rust resistance.

Cast iron cookware, when placed in a humid environment or soaked in water (moisture) is prone to rusting and oxidation. This means that in order to reuse the cookware it will have to be cleaned and re-seasoned to remove the rust (this involves scouring, washing with soap water, oiling and baking/heating the cookware).

Also read: How to remove stainless steel rust?

What are the benefits of cast iron over steel?

At this point you understand how iron and cast iron are different. But what are the differences between cast iron and steel? Let’s look at the benefits of cast iron over steel.

Benefits of cast iron over steel:

• Cast iron has excellent heat retention and distribution properties. Steel heats up and cools quickly but cast iron can retain heat for a longer period. This property makes it ideal for cooking applications, especially in Indian cooking.
• Compared to steel, cast iron is less expensive. For the budget conscious Indian market, cast iron is a cost-effective and durable solution.
• It is long lasting when properly maintained. This is advantageous when used in machine parts, manhole covers, and other applications subject to daily wear and tear. Unlike steel, it doesn’t wear, warp or dent easily.

Which is better iron or cast iron?

Considering the vast usage of both iron and cast iron, deciding which is better – iron or cast iron – depends on the application and requirements.

• Grills and railings: Iron is malleable and ductile and can be shaped into wires and sheets. They can accordingly be used for artistic metalwork such as making intricate grills and railings.
• Cookware: Cast iron is preferred in this case as it is durable, strong, and wear resistant. It is also a poor heat conductor which lets it heat slowly and distribute heat uniformly.

In brief, neither iron nor cast iron (nor steel) is better than the other. Each have unique properties and are used as per the benefits they bring.