Carbon structural steel: a type of carbon steel

Carbon structural steel, a kind of carbon steel. Carbon content is about 0.05% ~ 0.70%, individual can be up to 0.90%. Can be divided into ordinary carbon structural steel and high quality carbon structural steel two categories. Many uses, large amount, mainly used in railway, bridge, all kinds of construction engineering, manufacturing under static load of all kinds of metal components and not important do not need heat treatment of mechanical parts and general welding parts.

Representation method

The grade of carbon structural steel consists of four parts in order: the letter representing yield point, the value of yield point, the symbol of quality grade and the symbol of deoxidation method.

For example, Q235-A·F stands for grade A boiling steel with a yield point of 235Mpa, and Q235-C stands for grade C calm steel with a yield point of 235Mpa. Carbon structural steel is generally used in the supply state without heat treatment.

Mass fraction

Carbon structural steel is generally used in supply without heat treatment. Usually Q195, Q215, Q235 steel carbon quality fraction is low, good welding performance, plasticity, toughness, a certain strength, often rolled into sheet, steel bar, welded steel pipe, used in Bridges, buildings and other structures and manufacturing ordinary screws, nuts and other parts. Q255 and Q275 steel carbon quality fraction is slightly higher, higher strength, plasticity, toughness is better, can be welded, usually rolled into steel, strip steel and steel plate for structural parts and manufacturing of simple machinery connecting rod, gear, coupling, pin and other parts.

Mechanical property

This kind of steel mainly guarantees mechanical properties, so its brand reflects its mechanical properties, represented by Q+ numbers, where "Q" is the Chinese pinyin prefix of the yield point "Qu" character, the number represents the yield point value, for example, Q275 means the yield point is 275Mpa. If the letters A, B, C, D are marked after the grade, it means that the steel quality grade is different, the amount containing S and P decreases in turn, and the steel quality increases in turn. If the letter "F" is marked after the grade, it is boiling steel; if "b" is marked, it is semi-sedated steel; if "F" or "b" is not marked, it is sedated steel. For example, Q235-A·F represents grade A boiling steel with a yield point of 235Mpa, and Q235-C represents grade C calm steel or specially calm steel with a yield point of 235Mpa.