Cast iron sheet - metal for centuries

From blast furnace to modern production

Cast iron is one of the oldest alloys known to mankind. It was used to create the first machines, pipes, bridges, and machine tools.
Today, despite the spread of steel and aluminum, cast iron sheet remains a popular material.
Company AtomResource>> offers supplies of sheet cast iron of various thicknesses and compositions for industry, construction and mechanical engineering.

Modern cast iron sheet is the result of a combination of traditional metallurgy and new processing technologies. It is durable, robust, and ideal for work surfaces, housings, bases, and components subject to vibration and stress.

What is cast iron and how is it different from steel?

Cast iron is an alloy of iron and carbon, the carbon content of which exceeds 2 %. In addition to carbon, it contains silicon, manganese, sulfur, and phosphorus.
The main difference between cast iron and steel is its structure: while steel has a homogeneous metallic crystal lattice, cast iron consists of a metallic matrix with inclusions of graphite and cementite.

It is the graphite inclusions that give the material its unique properties—it becomes hard, yet capable of damping vibrations and retaining heat. When fractured, cast iron appears grainy and gray, and under a microscope, it resembles a stone mosaic—a light base with dark islands of graphite.

Production of cast iron sheets

To produce cast iron, blast furnaces are used – huge units in which iron is reduced from ore at a temperature of about 2000 °C.
Iron ore, coke, and fluxes are loaded into the charge. Air is supplied under pressure at the bottom of the blast furnace, and the ore oxides are reduced to iron, becoming saturated with carbon.

The resulting liquid iron is sent to foundries or rolling mills.
Depending on the processing method, the following is obtained:

• Cast sheet is dense and massive, with a natural surface;
• Rolled sheet is more even and uniform, used in mechanical engineering and parts production.

Types of cast iron sheets

There are several types of cast iron, which determine the properties of the sheets.

Gray cast iron is the most common. It contains lamellar graphite, which ensures good machinability and vibration resistance.
Malleable cast iron is obtained from white cast iron after a long annealing process, which makes it less brittle.
High-strength ductile iron (HSI) combines the strength of steel and the stability of cast iron and is used in critical components.
White cast iron contains almost no graphite, but it has extreme hardness – it is used in places where parts operate in abrasive conditions.

For sheet metal products, grey or ductile cast iron is most often used: they combine sufficient hardness with ease of mechanical processing.

Basic properties

Cast iron has a high density - about 7.2 grams per cubic centimeter.
Its thermal conductivity reaches 60 W/m K (meter Kelvin), which is higher than most steels, and its coefficient of thermal expansion is low, which ensures dimensional stability when heated.
The average hardness is 180–350 HB (Brinell hardness), and the melting point is about 1200 °C.

Cast iron's unique ability to dampen vibrations and noise is key. Therefore, many machine tools and measuring plates are made from cast iron sheets.

Comparison of cast iron with other metals

When comparing cast iron to other common materials, the differences are obvious.
It shares a similar composition with steel, but differs in its behavior under load: steel is more elastic and ductile, while cast iron is stiffer and better able to withstand compression. Furthermore, cast iron is less expensive and does not require complex heat treatment.

The contrast with aluminum is even stronger. Aluminum is lightweight, heats up quickly, and cools down just as quickly. Cast iron, on the other hand, is heavy and retains heat for a long time. Therefore, cast iron is chosen for applications where heat stability is important—for example, in stoves or molds.

Compared to copper and brass, cast iron wins in terms of price and strength, although it is inferior in thermal conductivity.

Why were engines previously made of cast iron?

For a long time, automobile engines had cast-iron cylinder blocks. This ensured durability and resistance to overheating—the block maintained its performance even when operating temperatures exceeded.
Over time, in an effort to reduce vehicle weight and improve fuel consumption, engineers switched to aluminum blocks. But even today, cylinder liners, crankshafts, and bearing assemblies are made of cast iron due to its hardness and dimensional stability when heated. However, downsizing and the deliberate reduction of resource consumption in the automotive industry are well-known facts.

Cast iron versus aluminum: in everyday life and technology

The same principles work in everyday use.
Cast iron radiators heat up slowly but retain heat for a long time – ideal for older heating systems and private homes.
Aluminum batteries are lighter, react faster to temperature changes, but also cool down faster.

It's the same with cookware: a cast iron cauldron or frying pan accumulates heat and ensures uniform heating.
Aluminum cookware is lighter but loses heat quickly, which interferes with consistent cooking. However, it is easier to store and handle during cooking—weight is a key consideration for home cooks.

What does cast iron look like at the structural level?

At the molecular level, cast iron is a metallic matrix of iron containing inclusions of graphite.
Unlike steel, where the structure is dense and homogeneous, cast iron contains many microvoids, phase boundaries and graphite veins.
This explains its high thermal conductivity and natural lubrication during processing – the tool seems to glide over the surface.

Interesting facts and history

The first cast iron was obtained in China as early as the 1st millennium BC.
The technology appeared in Europe much later, in the Middle Ages.
With the development of blast furnace production, cast iron became the basis of the Industrial Revolution: bridges, machines, and steam boilers were built from it.
The symbol of the era was the cast-iron Iron Bridge in England, built in 1779 and still in working order.

Cast iron sheet market

Russia is among the top ten largest producers of cast iron. The Central Federal District and Moscow account for the largest consumption, where mechanical engineering, foundries, and metalworking are highly developed.
Cast iron sheets are in demand in machine tool manufacturing for the production of equipment bases, support plates, and press and furnace parts.

Global demand is stable: thanks to its high density and wear resistance, cast iron remains indispensable where durability and heat resistance are required.

Cast iron sheets from AtomResurs

The scientific and production enterprise AtomResurs supplies cast iron sheets of various grades and formats.
The products undergo composition and surface quality control, comply with GOST requirements, and are intended for machining, milling, drilling, or installation as finished components.

Details are in the catalogue:
Cast iron sheet - https://atom-r.ru/catalog/list-chugunnyj/

Conclusion: material with character

Cast iron is a metal with personality. Heavy, calm, and reliable.
Cast iron sheet is the choice of those who value stability, durability, and physical strength of the material.
From machine tools to heating appliances, from molds to kitchen utensils, cast iron proves that classics never age, but improve.