Table of Contents
Steel is one of the key materials in the automotive industry. According to the World Steel Organisation, around 900 kg of steel is used per vehicle. Out of this, about 40% steel is used in body structures, doors and trunk closures; around 23% is used in drivetrains; and approximately 12% is used in suspensions and the remaining in wheels, fuel tanks, braking systems, etc. In brief, the importance of steel in the automotive sector can be seen in every part of the vehicle.
The steel used in each part of the vehicle is not of the same kind and grade. Each body part of the vehicle has a different role to play and according to its function, the requirement from steel varies. This article will deep dive into different types of steel used in the automotive industry and their roles.
Key features of steel for the automotive industry
Steel has some unique characteristics that makes it a suitable raw material in several industries. Not surprisingly, the growth of the steel sector in India has been phenomenal, with India ranking in the second position as the largest producer of crude steel.
Here are some key features of steel that makes it an important raw material from the automotive industry’s point of view.
- Strength: Steel is known for its strength and hence finds usage in various industries. For example, steel is an important raw material in construction, automotive, aerospace, and other sectors. Moreover, it is a hard material and can offer the required support to a small or large vehicle. On the other hand, it is lower in cost when compared to other materials exhibiting similar features. As a result, advanced high-strength steel (AHSS) turns out to be a popular choice for vehicle bodies.
- Safety: Along with strength, steel is also safer. Meaning, it can resist external damage to some extent. From the passenger’s point of view, this is one of the crucial features.
- Lightweighting: AHSS is a new generation of steel that is about 25-35% lighter than conventional steel. This makes it more sustainable and eco-friendlier as it improves the fuel efficiency of the vehicle. According to JSW Steel, a steel giant, the use of AHSS makes a passenger car about 170-270 kg lighter. This can translate into saving about 3-4.5 tonnes of greenhouse gases (GHG) during the car’s whole life span.
- Recyclability: Steel is a 100% recyclable material. It can be melted down and recovered without losing its quality.
Some of the other advantages that AHSS has include durability while maintaining formability. These are some crucial benefits from the manufacturing point of view as well. This makes steel a significantly important material in the production of a vehicle’s framework or skeleton of the car’s body.
Steel in the vehicle framework
Although steel is used in mostly all kinds of vehicles including two-wheelers such as scooters and motorcycles, passenger cars to larger vehicles such as buses, the raw material requirements change as per the vehicle. Here is the role of steel in a varied type of vehicle’s framework.
Passenger car’s framework
Framework of the vehicle is the most important part of the car as it withstands pressure, varied weather conditions, etc. Also, it needs to enhance the safety of the passengers inside. Since the framework is the basic structure of the car, it directly impacts the performance of the car too. Considering these expectations, advanced high-strength steel (AHSS) is used for the vehicle’s framework.
As per the industry standards, the car body requires minimum tensile strength of 440 MPa. AHSS fits this criterion too. Moreover, it helps in lightweighting the vehicle which leads to better fuel efficiency. Therefore, AHSS is preferred to be used in the vehicles’ framework globally.
Key function of the motorcycle framework is to support all the other parts such engine, fuel tank, seat, suspension, etc. Steel, when used in a motorcycle’s framework does not only offer the required strength to hold all the parts of the motorbike but also offers flexibility in design. Meaning required curvature and aesthetic appeal can be achieved with the use of steel.
Also, corrosion on steel can be restricted with coatings and treatments. Depending on the manufacturing cost and considering other economic aspects of production, other materials such as carbon fibre are also used for the motorcycle’s framework in some cases. However, carbon fibre is not a cost-effective material.
Framework for large vehicles
Large vehicles such as buses need to withstand high pressure, weight, etc. Steel meets these requirements and makes these buses safer too. As a result, AHSS is widely used in the framework of buses.
What are other types of steels used in the automotive industry?
Although AHSS is mostly used for car body structures, there are various other kinds of steel used in other applications of the automotive industry. Here are some of the types of steel that are used in the automotive industry.
- Stainless steel: Stainless steel is capable of withstanding high temperatures and also it is durable. As result, it is commonly used in components such as engines, exhaust systems, etc.
- High carbon steel: As the name suggests, it contains high level of carbon content and undergoes a heat treatment called quenching. It is a wear and tear resistant material and hence, it is used in tools, fasteners, bushing, and so on.
- Galvanised steel: It is yet another commonly used steel in the automotive industry. Galvanised steel is coated with a thin layer of zinc, which protects it from corrosion. Also, it is maintenance free. Since galvanised steel prevents corrosion, it can be used in exteriors, interiors or underbody parts of the vehicles.
- Low-carbon steel: Unlike high carbon steel, low carbon steel contains a minimal level of carbon. It is known for ductility and lower tensile strength. It is easier to give low carbon steel desired shape. Hence, is useful in making smaller components like suspension parts, brackets, and so on.
Takeaways in a nutshell
Depending on the type of the vehicle, expected usage of the vehicle and manufacturing costs, different types of steel is used in the automotive industry. However, steel remains one of the major materials in any vehicle. Therefore, the role of the steel in the automotive industry is undebatable. One can easily start an automobile business since raw material is widely available in India..