Why Is Steel Used for Car Bodies?

Steel is used extensively in car bodies.

Steel is commonly used in the construction of the chassis and body panels of trucks and automobiles. The reason for steel's use in the automotive sector is steel's unique set of characteristics as a construction material.

Material Properties

Steel consists mainly of iron with a small amount -- between 0.2 and 2.1 percent -- of carbon. Steel is very hard and strong. Steel has a very high strength to weight ratio. All these properties make it suitable as a material for car bodies. Steel is often alloyed with small quantities of manganese, chromium, tungsten and vanadium to make it even stronger.

Ease of Manufacture

Because steel is malleable, it is capable of being shaped into the forms needed to create the chassis and body panels of automobiles. Steel is able to be poured into molds and cooled to create other forms, such as an engine block. And steel is easy to bond together using welding techniques.

Cost

The price of steel is low relative to many other metals. Although aluminum is lighter than steel and has a similar strength-to-weight ratio, it is significantly more expensive and so is only used in high-end automobiles. Steel is plentiful and cheap. When combined with its material characteristics and its malleability, these factors make it an ideal choice for car bodies.

References

• Automotive Design and Production: Better Vehicles Through Steel
• Bluescope Steel: Properties of Steel
• Efunda: Steels in General
• American Iron and Steel Institute: Steel Glossary