Alloy Steel: Everything you need to know about alloy steels and their role in building and construction industry

An overview of `steel`

Steel is among the most popular materials used in the construction industry. According to the World Steel Association, in 2018 around 1,808 million tons of crude steel was produced worldwide and about 50% of this production was utilized by the construction industry. Further, they also state that there are as many as 3,500 different grades of steel and each grade offers environmental, chemical and physical properties unique to that grade of steel. and each grade offers environmental, chemical and physical properties unique to that grade of steel. Steel has undergone significant evolution through time and around 75% of all the types of modern-day steel were developed in the past 20 years and developed instantly. It is interesting to note that had the Eiffel Tower (constructed in 1887) been constructed in today`s times, it would require only one-third of the steel used back then.

Fundamentally, steel is an alloy of iron with low amounts of carbon. There are thousands of different types of steels which are created to suit different kinds of applications. These broadly fall into 4 types – Carbon Steel, tool steel, stainless steel and alloy steel. Carbon steels form the majority of steels produced in the world today. Tool steels are used to make machine parts, dies and tools, etc. Stainless steels are used to make common household items. Alloy steels are made of iron, carbon and other elements such as vanadium, silicon, nickel, manganese, copper and chromium.

Alloy steel

When other elements comprising metals and non-metals are added to carbon steel, alloy steel is formed and takes the parts of big steel market gradually. These alloy steels display various environmental, chemical and physical properties that can vary with the elements used to alloy. Here the proportion of alloying elements can provide different mechanical properties.

Effects of alloying

Alloying elements can alter carbon steel in several ways. Alloying can affect micro-structures, heat-treatment conditions and mechanical properties. Today`s technology with high-speed computers can foresee the properties and micro-structures of steel when it is cold-formed, heat treated, hot-rolled or alloyed. For instance, if properties such as high strength and weldability are required in steel for certain applications, then carbon steel alone will not serve the purpose because carbon`s inherent brittleness will make the weld brittle. The solution is to reduce carbon and add other elements such as manganese or nickel. This is one way of making high strength steel with required weldability.