Classification of steel

The finished material

Building materials - rebar, wire, coil, round steel

Pipe -- seamless pipe, welded pipe

Plate: cold and hot rolled plate/coil, medium thick plate, color coated plate (galvanized plate, color coated plate, tin plate, aluminum zinc plate), silicon steel, strip steel

Profile - Angle slot, H - shaped steel, square steel, flat steel, flat ball steel

Special steel

: structural steel, tool steel, die steel, spring steel, bearing steel, cold heading steel, hard wire

Steel is an iron-carbon alloy with carbon content between 0.0218 percent and 2.11 percent. In order to ensure its toughness and plasticity, the carbon content is generally not more than 1.7 percent. In addition to iron and carbon, the main elements of steel are silicon, manganese, sulfur and phosphorus. There are a variety of steel classification methods, the main methods are as follows:

1. Classification by quality

Carbon steel: a. Low carbon steel (C≤0.25 percent); B. Medium carbon steel (0.25≤C≤0.60 percentage points);

C. High carbon steel (C≥0.60 %).

Low alloy steel (total alloying element content <5 percent); B. Medium alloy steel (5 percent ≤ total alloying element content ≤10 percent); C. High alloy steel (total alloying element content >10 percent).

2. Classification by forming method :(1) forged steel; (2) cast steel; (3) hot rolled steel; (4) Cold drawn steel.

4. Classification according to metallographic organization

Annealed: a. Hypoeutectoid steel (ferritic + pearlite); B. Eutectoid steel (pearlite); C. Eutectoid steel (pearlite + cementite); D. Lastenitic steel (pearlite + cementite).

Normalizing: a. Pearlite steel; B. Bainitic steel; C. Martensitic steel; D. austenitic steel. (3) having no or partial phase transition

5. Classification by use

Engineering steel: a. Common carbon structural steel; B. Low alloy structural steel; C. Reinforced steel.

Carburized steel: a. Nitriding steel; B. Surface hardened steel; C. Shear structural steel; D. Steel for cold plastic forming: including steel for cold stamping and steel for cold heading.

Carbon tool steel; A. Alloy tool steel; B. High speed tool steel.

Special performance steel: a. Stainless acid resistant steel; B. Heat resistant steel: including chemical steel, thermal strength steel, valve steel; C. Electrothermal alloy steel; D. Wear resistant steel; E. Low temperature steel; F. Electrical steel.

Bridge steel, ship steel, boiler steel, pressure vessel steel, agricultural machinery steel, etc.

6. Comprehensive classification

Fine steel

(including good steel)

Structural steel :(a) good carbon structural steel; (b) alloy structural steel; (c) Spring steel; (d) Easy cutting steel; (e) Bearing steel; (f) Good structural steel for specific purposes.

Tool steel :(a) carbon tool steel; (b) alloy tool steel; (c) High speed tool steel.

Special performance steel :(a) stainless acid resistant steel; (b) Heat-resistant steel; (c) Electrothermal alloy steel; (d) Electrical steel; (e) High manganese wear resistant steel.

7. Classification by smelting method

Electric furnace steel :(a) electric arc furnace steel; (b) electroslag furnace steel; (c) Induction furnace steel; (d) Vacuum consumable furnace steel; (e) Electron beam furnace steel.