Steel is a versatile alloy primarily composed of iron and carbon, with various other elements added to achieve specific properties. Below are the main types and variations of steel:
- Carbon Steel
Low-Carbon Steel (Mild Steel): Contains up to 0.25% carbon. It’s ductile, malleable, and used in construction and automotive parts.
Medium-Carbon Steel: Contains 0.25–0.60% carbon. It offers a balance of strength and ductility and is used for gears and railway tracks.
High-Carbon Steel: Contains 0.60–1.5% carbon. It’s hard and brittle, often used for cutting tools and springs.
- Alloy Steel
Steel with elements like chromium, nickel, vanadium, molybdenum, or manganese to enhance specific properties.
Examples:
Chromium Steel: Improved wear and corrosion resistance.
Nickel Steel: Enhanced toughness and low-temperature performance.
- Stainless Steel
Contains at least 10.5% chromium, which provides corrosion resistance.
Types of Stainless Steel:
Austenitic: Non-magnetic, highly corrosion-resistant (e.g., 304 and 316 grades).
Ferritic: Magnetic and corrosion-resistant, but less ductile.
Martensitic: Magnetic, high strength, used in cutlery.
Duplex: A mix of austenitic and ferritic, offering strength and corrosion resistance.
Precipitation-Hardening: Excellent strength with moderate corrosion resistance.
- Tool Steel
High hardness and resistance to abrasion, used for tools, dies, and molds.
Common types:
High-Speed Steel (HSS): For cutting tools.
Water-Hardening (W-Grade): Affordable and used in low-heat applications.
Shock-Resistant Steel (S-Grade): Handles high-impact applications.
- Specialty Steels
Maraging Steel: Ultra-high strength and toughness, used in aerospace and tooling.
Weathering Steel (Corten Steel): Forms a protective rust layer, used in outdoor structures.
Electrical Steel: Used in transformers and motors for its magnetic properties.
- Galvanized Steel
Coated with zinc for rust resistance, commonly used in roofing and fencing.
- Spring Steel
High elasticity and fatigue resistance, used in springs and suspension systems.
Each variation is tailored for specific applications by adjusting the composition and processing methods.