Steel

Basic Definition

Steel is an iron-carbon alloy containing less than 2.11% carbon by mass, mixed with other alloying elements such as chromium, nickel, manganese and silicon. It is the most widely used structural metal worldwide.

Core Characteristics

• High tensile strength and hardness, excellent load-bearing capacity for heavy-duty structures.
• Good machinability, weldability and formability, suitable for casting, forging, stamping and CNC machining.
• Cost-effective raw material compared with aluminum, titanium and copper alloys.
• Ordinary carbon steel easily oxidizes and rusts in humid or salty air; alloy steels like stainless steel gain strong anti-corrosion performance.
• Wide adjustable properties: carbon content and alloy composition can be modified to make soft ductile steel or ultra-hard wear-resistant steel.

Main Classifications

1. Carbon Steel Low/medium/high carbon grades. Cheap, strong, easy to process, used for machinery frames, molds, construction steel, fasteners. Poor rust resistance without coating.
2. Stainless Steel (Alloy Steel) With chromium and nickel additives (304, 316, 430 etc.). A protective chromium oxide passive film forms automatically on surface, resisting rust, acid and seawater. Common for medical parts, food equipment, pipelines and decorative hardware.
3. Alloy Structural Steel / Tool Steel Added molybdenum, vanadium etc. High hardness and wear resistance, applied to cutting tools, gears, bearings and hydraulic parts.

Common Surface Treatments

Sandblasting, painting, powder coating, electroplating, hot-dip galvanizing, electropolishing (for stainless steel only).

Typical Applications

Construction frames, automobile parts, molds, fasteners, mechanical equipment, stainless sanitary fittings, ship components, cutting tools.

Material parameters