Q235 Steel Q235A Q235B Q235C Q235D Properties, Specification, Composition
Q235 steel is a plain carbon structural steel widely used in China. According to the Chinese standard GB/T 700, Q235 material is divided into four quality grades: Q235A, Q235B, Q235C, and Q235D. The density of this steel is 7.85 g/cm³ (0.284 lb/in³), with a tensile strength of 370-500 MPa (54-73 ksi) and a yield strength of 235 MPa (34 ksi) for steel bar diameter or plate thickness ≤ 16mm. As it is mild steel, the material is commonly used directly without heat treatment. Q235 material has moderate strength, and in cases requiring higher strength, Q275 or high-strength low alloy structural steel Q355 (formerly Q345) can be selected.
Q235b Meaning and Designation
“Q” is the first letter of Chinese spelling of “Qufu dian”, which means Yield Point.
“235” refers to the minimum yield strength 235 MPa tested with steel bar diameter or plate thickness ≤ 16mm.
A, B, C and D represent quality grades.
Carbon Steel q235b
Features and Applications
Q235 steel stands out for its remarkable plasticity, toughness, and weldability, coupled with a balanced strength and exceptional cold bending capabilities. This material is commonly shaped into various forms including wire rods, round, square, and flat bars, as well as angle beams, I-beams, and channel beams, besides being made into steel plates. Its application is extensive in the fields of construction and engineering, especially in welded structures. It is integral to the manufacturing of steel bars or the construction of industrial buildings, electrical transmission towers, bridges, vehicles, boilers, containers, and more. Additionally, Q235 steel is utilized for mechanical components that do not require high stress tolerance, such as lightly stressed rods, connecting rods, screws, nuts, ferrules, brackets, and supports.
The table below lists Q235 material chemical composition based on heat analysis.
Q235 Steel Chemical Composition
Steel Grade | Quality Grade | C (%) | Si (%) | Mn (%) | P (%) | S (%) | Deoxidation Method |
---|---|---|---|---|---|---|---|
Q235 | Q235A | 0.22 | 0.35 | 1.40 | 0.045 | 0.050 | Rimmed / Killed |
Q235 | Q235B | 0.20 | 0.35 | 1.40 | 0.045 | 0.045 | Rimmed / Killed |
Q235 | Q235C | 0.17 | 0.35 | 1.40 | 0.040 | 0.040 | Killed |
Q235 | Q235D | 0.17 | 0.35 | 1.40 | 0.035 | 0.035 | Exceptionally Killed |