Steel - Building material

Material introduction

Steel is a material of a certain shape, size and properties made from ingot, billet or steel by pressure working. Most steel processing is through pressure processing, so that the processed steel (billet, ingot, etc.) produce plastic deformation. According to the different steel processing temperature, can be divided into cold processing and hot processing two.

Steel: The material of ingot, billet, or steel that is pressed into a variety of shapes, sizes, and properties.

Steel is an essential material for national construction and the realization of the four Modernizations. It is widely used and in various varieties. According to the different section shapes, steel is generally divided into four categories: profile, plate, pipe and metal products, and also divided into heavy rail, light rail, large section steel, medium section steel, small section steel, cold formed steel. High quality section steel, wire, medium thickness steel plate, thin steel plate, electrical silicon steel sheet, strip steel, seamless steel pipe steel, welded steel pipe, metal products and other varieties.

characteristic

Ferrous metal

Ferrous metals mainly refer to iron, manganese, chromium and their alloys.

Iron and steel

The pig iron used in steelmaking is put into the steelmaking furnace and smelted according to a certain process, that is, steel is obtained.

Non-ferrous metal

Metals other than ferrous metals are called non-ferrous metals, such as copper, tin, lead, zinc, aluminum, as well as brass, bronze, aluminum alloy and bearing alloys.

classification

Finished material

Building materials - bar steel, wire, disc screw, round steel

Pipe - seamless pipe, welded pipe

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

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

Special steel

Including 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% and 2.11%. In order to ensure toughness and plasticity, the carbon content is generally no more than 1.7%. In addition to iron and carbon, the main elements of steel are silicon, manganese, sulfur, phosphorus, etc. Steel is classified in a variety of ways, the main methods are as follows:

1. Classification by quality

Ordinary steel: (P≤0.045%, S≤0.050%);

High quality steel: (P, S≤0.035%);

High quality steel: (P≤0.035%, S≤0.030%).

2. Classification by chemical composition

Carbon steel: a. mild steel (C≤0.25%); b. Medium carbon steel (0.25≤C≤0.60%);

c. High carbon steel (C≥0.60%).

Low alloy steel (total alloying element content < 5%); b. Medium alloy steel (5%≤ total alloying element content ≤10%); c. High alloy steel (total alloying element content > 10%).

3, according to the forming method classification: (1) forging steel; (2) cast steel; (3) hot rolled steel; (4) cold drawn steel.

4. Classification by metallographic organization

Annealed: a. hypoeutectoid steel (ferritic + pearlite); b. Eutectoid steel (pearlite); c. Hypereutectoid steel (pearlite + cementite); d. Leytenite steel (pearlite + cementite).

Normalizing: a. pearlite steel; b. Bainitic steel; c. Martensitic steel; d. austenitic steel. (3) No phase transition or partial phase transition

5. Classification by use

Engineering steel: a. Ordinary carbon structural steel; b. Low alloy structural steel; c. Reinforcing steel.

Carbon steel: a. Nitriding steel; b. Steel for surface hardening; c. Easy cutting structural steel; d. Steel for cold plastic forming: including steel for cold stamping and cold heading.

Carbon tool steel; a. Alloy tool steel; b. High speed tool steel.

Steel with special properties: a. stainless acid-resistant steel; b. Heat-resistant steel: including anti-oxidation steel, heat-strength steel, valve steel; c. Electrothermal alloy steel; d. Wear-resistant steel; e. Steel for low temperature; f. Steel for electrical purposes.

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

6. Comprehensive classification

High quality steel

(including high quality steel)

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

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

Steel with special properties: (a) stainless and acid-resistant steel; (b) heat-resistant steel; (c) electrothermal alloy steel; (d) Steel for electrical purposes; (e) High manganese wear-resisting steel.

7. Classification by smelting method

Electric furnace steel: (a) electric furnace steel; (b) electroslag steel; (c) induction furnace steel; (d) vacuum consumable furnace steel; (e) electron beam furnace steel.