Mild Steel: Properties and Various Uses

Steel is the most commonly used metal in the world, and for good reason. For many applications, it offers the perfect combination of strength, cost, and ease of manufacture. But what is it that makes steel so useful, and what are some common uses?

What is Mild Steel and its Key Properties?

Humans have been creating things out of metal for thousands of years. First, it was Copper, then Bronze, then Iron. By 1856, a new process was developed by Henry Bessemer, which allowed steel to be made in great quantities. It soon became the material of choice for industrial applications the world over.

Mild steel is characterized by:

• Good tensile strength – this enables it to be used for bridges, structures, and other load-bearing components; it is around 3-5x stronger than cast iron
• High weldability – it can be readily welded by all processes, and high-strength bonds are easily achieved
• Ductility – its high ductility makes it easy to form into shaped sections, and bending in sheet form is accurate and repeatable
• Low cost – mild steel is considerably cheaper than aluminum, stainless steel, copper, and any other nonferrous metals

Mild Steel vs. Other Steels: Understanding the Differences

Mild steel is a term generally used to describe low-carbon steel, composed primarily of Iron and between 0.05% and 0.3% carbon. Other alloying elements are added to improve strength, ductility, and other properties, such as manganese, silicon, and copper.

Steel can be categorized into 4 groups: Carbon steel (including mild steel), alloy steel, stainless steel, and tool steel.

Carbon Steel

The term carbon steel is used to describe the general structural steels commonly used in fabrication, these range in tensile strength from 235MPa to over 500MPa. They typically only contain carbon and a few trace elements such as manganese, phosphorus, etc.

Alloy Steel

Often considered specialty materials, these are still composed mostly of iron and carbon, but have other alloying elements in them too, such as NiCrMo in EN24, and NiCrMn in EN36. These steels vary in their properties, with some being noted for their surface hardness and others for their tensile strength.

Stainless Steel

The defining feature of stainless steel is generally considered to be its Chromium content. Typical stainless steels, such as 316 grade, have around 18% Cr, with all stainless grades having a minimum of 10%. Stainless steel is revered for its corrosion resistance, being impervious to conditions that would cause mild steel to rust away.

Tool Steel

As the name suggests, tool steel is generally used for any components that are used to work with other metals. Their high carbon content makes them good for this, giving excellent hardness and abrasion resistance. The various grades of tool steels are used to make everything from drill bits to saw blades.

Common Uses of Mild Steel in Various Industries

Mild steel is everywhere in industry, from the buildings we work in to the cars we drive, low carbon steel is what makes up the bulk of components fabricated from metal, here are some industry-specific uses.

Construction

One of the largest uses of mild steel is in steelwork for buildings, beams, columns, channels and even sheet metal cladding will all be made from low-carbon steel. It is used for its strength, low cost, and ease of manufacture.

Typically, mild steel used in construction will be galvanized or painted, to protect it from corrosion. You will also find mild steel, often in sheet form, in HVAC, electrical, and roofing applications.

Automotive

Parts such as body panels, chassis, suspension components, and bracketry will be made of low carbon/mild steel, as well as the exhaust system. Its formability and cost make it perfect for the bodywork and structure, and its high ductility and toughness make it perfect for suspension components.

Aerospace

Whilst mild steel strength-to-weight ratio is not good enough to be used in aircraft, the machines that assist in manufacturing them, alongside the ground support vehicles, tugs, tankers, stair trucks, etc, will all use a lot of mild steel components, not to mention the buildings and hangars they are built in!

Food Production

Because of mild steel’s low corrosion resistance, it cannot typically be used anywhere a hygienic finish is required, which is most areas in food processing plants.

Mild steel is used extensively however, the industries that supply such plants, agriculture, fishing, packaging, etc, all utilize mild steel in many ways, from the tools used to the trucks that ship the product.

Advantages of Using Mild Steel: Why Choose It?

The primary driving force behind the use of mild steel is cost. It is not only cheap in raw form, but relatively inexpensive to manufacture. Because of its widespread use, machinery to cut, bend, weld, machine, and form mild steel is readily available at just about every price point and accuracy level.

Another key factor, especially compared to more traditional materials such as wood, is its high strength-to-cost ratio. High levels of automation with CNC and other technologies have made it easier than ever to make components from steel.

Mild Steel: Cost, Maintenance, and Sustainability Considerations

We’ve touched on the cost of buying and processing mild steel, but this is not the whole story. Because it is not corrosion resistant, like stainless steel, it needs to be protected if it is to last a prolonged period.

This is typically done by galvanizing, painting, or a combination of both. This gives good protection against the elements by applying a layer of molten zinc to the surface. The downside to this is cost, lead time, and the inability to alter components after they have been treated.

Like most metals, sustainability is yet another plus point for mild steel. Thanks to its ease of recycling and relatively high value, end-of-life components such as building structures, or even old vehicles, are worth melting down and reusing. This reduces the need for mining and processing of the raw materials used to make steel.

Get your Mild Steel from Metals Supermarket

Whether you need sheet metal for a repair or structural steel for new construction work, Metals Supermarket can offer great prices and a cut-to-length service across our stores nationwide.