Steel is an alloy primarily composed of iron and a small amount of carbon (typically less than 2%). It is the most widely used material for global infrastructure, industry, and transportation because it is relatively inexpensive to produce and offers an unparalleled range of mechanical properties.
Key Types of Steel
While there are over 3,500 grades of steel, they are generally grouped into four main categories: [
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- Carbon Steel: Accounts for about 90% of global production.
- Low Carbon (Mild Steel): Easy to shape and weld; used for car body panels, pipes, and general construction.
- Medium Carbon: Balanced strength and ductility; used for gears, axles, and railway tracks.
- High Carbon: Extremely hard and strong but brittle; used for springs and cutting tools.
- Alloy Steel: Contains additional elements like manganese, silicon, nickel, or chromium to enhance specific properties like toughness or wear resistance.
- Stainless Steel: Contains at least 10.5% chromium, which creates a protective layer to resist corrosion. It is used for medical instruments, kitchenware, and architectural fittings.