Difference Between Steel and Cast Iron (With Table)

Metals are of great demand not only in today’s world but ever since it was discovered in the first place. It is the different kinds of uses that create the huge demand for metals such as steel and iron. We all know what and where they are used.

However, there is a huge difference between steel and cast iron when they are compared together. Steel is much more expensive than iron although steel is created from impurities that have been removed from iron itself. So, you can imagine that without iron there is no steel.

Steel vs Cast Iron

The difference between steel and cast iron is the carbon content in them. Iron is an element whereas steel is just a by-product of iron. Cast iron contains more than 2 percent of carbon whereas steel only has between 0.1-0.5 percent. You might know that more the content of carbon higher the iron will be malleable.

The presence of carbon in iron more than 4% makes cast-iron whereas steel will contain less than 2% of carbon. So, the main distinction between these two is the presence of carbon in them.

Comparison Table Between Steel and Cast Iron

Parameters of ComparisonSteelCast Iron
DefinitionSteel is called an alloy of iron.Cast iron is also an alloy of iron.
Presence of CarbonSteel has got fewer presence of carbon approximately less than 2%.Cast iron has got more than 2% of carbon approximately more than 4%.
PropertiesDuctile and malleableThe random motion of molecules.
Form of carbonIron carbideGraphite or iron carbide or can be both.
Melting pointMore than cast ironLower than steel.
FluidityNo fluidityExcellent fluidity

What is Steel?

Steel is an alloy of iron. It has got a large number of uses in today’s world and is in huge demand too. You see in products like scissors, blades, and other utensils stainless steel is used. Steel’s carbon presence is very less approximately less than 2%.

Surprisingly, steel is made from the impurities or the slag that has been removed from iron itself. So, in other words, it means that without iron you cannot have steel. Steel is just an alloy whereas iron is an element that is found abundantly in most rocks, can be found even on meteoroids.

There is a process of making steel but iron is found naturally on Earth’s surface or in any other space. However, you will be surprised to know that cast iron is cheaper than steel with a very low melting point. As steel can be melted it can be turned into any shape or form and when it becomes cold there is no shrinkage.

This is how several products and utensils are made using steel by melting them and making them into several forms and shapes. The presence of carbon in steel is less as compared to cast iron. Stainless steel is just another grade of steel where metals like chromium are added to get the result.

Steel’s properties also vary from cast iron’s properties because steel is much milder and they are harder to cast. Steel also has a high viscosity meaning (a measure of a fluid’s resistance to flow).

What is Cast Iron?

Cast iron, on the other hand, is a group of iron and carbon alloys that has got a carbon content of more than 4%. Iron is a hard metal and is found abundantly on Earth’s surface. Scientists have even found iron on meteoroids. The presence of carbon is the main difference between cast iron and steel.

However, other than that both of the properties for both these two types of metals are different from each other. Cast iron is cheaper than steel and the properties of iron are that they are brittle and can absorb vibrations and noises too.

Iron, when molten could be cast into different forms by using the components of several machines to more complicated shapes like cast iron gates. However, iron can be destructive in nature when they are drilled. It can produce power and it does not bend due to their hardness.

Main Differences Between Steel and Cast Iron

  1. The only huge difference between steel and cast iron is the presence of carbon.
  2. Steel has approximately less than 2% of presence of carbon whereas cast iron has got more than 4% carbon.
  3. Cast iron is much harder than steel.
  4. Steel has no fluidity whereas cast iron is excellent fluidity.
  5. Melting point of steel is more than cast iron and the melting of cast iron is less than steel.
  6. Iron is an element whereas steel is just an alloy.
  7. Iron is found abundantly and can even be found in meteoroids whereas steel is the scrap from iron.


 Both these metals have a great usage in today’s world and are in huge demand. Steel is much pricey than cast iron and has a great value in the market today. Both these metals have different usage because they have different properties.

Cast iron is mainly used for making pipes, guttering, and manhole covers whereas steel is used for making tools like knives, spoon, scissors, and other such materials. Steel is a great demand in the automobile industry because steel is made for making construction materials or parts in a car.

Many people think that steel is harder than cast iron and many people think that iron is much harder. But, it is cast iron that is harder than steel.


  1. https://books.google.com/books?hl=en&lr=lang_en&id=6ZgvRtOvMvUC&oi=fnd&pg=PA3&dq=steel+and+cast+iron&ots=10OOb9aYW-&sig=nl2qY9aodRyolCcQs4OSahpYxLs
  2. https://meridian.allenpress.com/corrosion/article-abstract/14/6/43/157351
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