The main component in the manufacturing of Mild Steel (also known as Low Carbon Steel) is Iron Ore. Although Iron (Fe) forms the major component of Low Carbon Steel, other elements are added to ensure certain physical properties are achieved.

Classification of Low Carbon Steel

The Society of Automotive Engineers (SAE) uses a four-digit numeration system to classify steel. The first number generally indicates whether the steel is a plain Carbon type one, whereas the second number indicates the type of modification the steel has undergone.

The last two digits simply indicate the steel’s Carbon composition. For example “SAE 1008” indicates the steel contains 0.08% carbon, whereas “SAE 1010” indicates the steel contains 0.10% carbon.

Effects of different Alloying Elements

Thus far the discussion has indicated that Low Carbon Steel consists of Iron and Carbon. However, there are a few more important elements required to ensure that Low Carbon Steel can perform as required.

Table 1: Impact of Alloying Elements

Mild Steel can be coated with an advanced Aluminium-Zinc-Silicon alloy, ensuring a coated product with exceptional corrosion protection, formability and an amazing 100% recycling capability – all at cost effective prices.

Furthermore, new advanced paint systems such as Polyvinylidene and Polyurethane enable this product to be used in high corrosion applications.

The steel industry’s scope

The steel industry has an estimated R14 trillion annual turnover making it the second largest industry in the world after oil and gas.

Due to Mild Steel being able to reach tensile strength greater than 570 MPa at relatively low cost, it is a major component used in almost every industry including energy, construction and housing, automotive and transportation, infrastructure, packing, and machinery. 75% of all major appliances are made of steel.

The construction and housing sector is the largest consumer of steel worldwide, using around 50% of all steel produced.

Steel in Building

Steel’s characteristics make it an excellent fit for the building industry, with steel roofs lasting more than 50 years compared to traditional roofs which last about 17 years. Furthermore, time-related savings from steel construction can account for 3-5% of the total project value.

Steel bridges are four to eight times lighter than those built from concrete. The Golden Gate Bridge (completed in 1937) required 83 000 tons of steel whereas half of that amount would be needed today thanks to lighter forms of steel being developed over the past century.

Thanks to the ferromagnetic properties of many steel alloys, they are very easy to remove from the solid waste stream and divert into recycling plants. Virtually no matter how many times steel is reprocessed, it will retain its properties (including its strength), making it an exceptionally sustainable material.

Since World War II, the worldwide steel industry has significantly reduced its energy use which has contributed to a major reduction in carbon dioxide generation. Recycling steel today saves at least 75% of the energy that it would take to create steel from raw materials.

Steel recycling is particularly prevalent in the canned goods sector where two-thirds of all packaging is made out of steel. It takes as little as 6 weeks for a drink can to be recycled, and be back on the supermarket shelf in the form of another can. This is no small feat as recycling a single steel can save enough energy to power a 60-watt light bulb for almost 4 years.

Note:

With its high strength, relatively low cost and exceptional sustainability record, steel looks set to be a bedrock of economic growth and activity for the indefinite future. Furthermore, as climate change concerns hasten the move to using ‘greener’ materials, we should see the steel industry continue to evolve and expand – and evolution in steels continue to make them more useful than ever before.