Q235 steel
Q235 steel
Q235 is a common carbon structural steel in China, also known as A3 plate. (GB / 700-1999). "Q" is the first letter of Chinese spelling of "Qu Fu Dian", translated as Yield Strength, "235" is a abbreviation for the unit value "235 MPa" (It is an experimental value measured with a 16mm steel bar), so it is called Q235 steel.
The yield strength value of Q235 steel will decrease as the material thickness increases
Quality grade of Q235 steel
Q235 steel quality grade symbols are A, B, C, D (Q235A, Q235B, Q235C, Q235D). The sulfur content of Q235A, Q235B, Q235C, and Q235D decreases in turn; the phosphorus content of Q235A and Q235B is the same, the phosphorus content of Q235C is second, and the phosphorus content of Q235D is the least
Symbols of deoxidation method: F means boiling steel; b means semi-killed steel: Z means killed steel; TZ means special killed steel. The symbols for killed steel can be omitted, that is, Z and TZ can be omitted. For example Q235-AF stands for Class A boiling steel.
Deoxygenation method
Q235A and Q235B steels each have three deoxidation methods, F, b and Z. Q235C steel is only killed steel, Q235D steel is only special killed steel. Boiling steel is a steel with incomplete deoxidation, and has poor plasticity and toughness. The welded structure made of this material is prone to cracks in the joint when subjected to dynamic loads. It is not suitable to work at low temperatures, and sometimes hardening occurs. In contrast, sedative steel is superior and homogeneous, with good ductility and toughness.
Q235 steel Chemical composition
Q235 steel Mechanical properties
Q235 steel Minimum Elongation
Q235 steel Minimum Charpy Impact
The different grades of Q235A, Q235B, Q235C, and Q235D represent mainly different impact temperatures. A means no impact, B is above 20 degrees, C is above 0 degrees, and D-20 is above. The difference between A and E refers to the difference in impact temperature in their performance. They are: Q235A grade, which is not required for impact toughness test; Q235B grade, which is used for normal temperature (20 ℃) impact toughness test; Q235C grade, which is used for 0 ℃ impact toughness test; Q235D grade, which is used for -20 ℃ impact toughness test. The impact toughness test uses Charpy V-notch test pieces. The impact toughness index is Akv. For the above-mentioned B, C, and D steels, under their respective different temperature requirements, Akv≥27J is required. The impact value varies at different impact temperatures.
Q235 Steel Bending Test Results
B=Sample Steel Width a=Sample Diameter or Thickness
Q235 Steel Equivalent grade
Q235 die steel quenching
The quenching temperature is 950 ° C, the salt bath furnace is heated, and the 10% NaCl brine is cooled and quenched.
Application of Q235 steel
Q235 steel is widely used because of its low carbon content, good comprehensive properties, and good combination of strength, plasticity, and welding properties.
1. Q235 steel is widely used in construction and engineering structures. It is used to make steel bars or to build factory buildings, high-voltage transmission towers, bridges, vehicles, boilers, containers, ships, etc., and is also used in large quantities as mechanical parts with less demanding performance. Q235C, Q235D grade steel can also be used as some professional steel.
2. Q235 steel can be used for various mold handles and other insignificant mold parts.
3. Q235 steel is used as the punch material, and it is used directly after quenching without tempering. The hardness is 36 ~ 40HRC, which solves the phenomenon that the punch is broken in use.
Q235 is a common carbon structural steel in China, also known as A3 plate. (GB / 700-1999). "Q" is the first letter of Chinese spelling of "Qu Fu Dian", translated as Yield Strength, "235" is a abbreviation for the unit value "235 MPa" (It is an experimental value measured with a 16mm steel bar), so it is called Q235 steel.
The yield strength value of Q235 steel will decrease as the material thickness increases
Quality grade of Q235 steel
Q235 steel quality grade symbols are A, B, C, D (Q235A, Q235B, Q235C, Q235D). The sulfur content of Q235A, Q235B, Q235C, and Q235D decreases in turn; the phosphorus content of Q235A and Q235B is the same, the phosphorus content of Q235C is second, and the phosphorus content of Q235D is the least
Symbols of deoxidation method: F means boiling steel; b means semi-killed steel: Z means killed steel; TZ means special killed steel. The symbols for killed steel can be omitted, that is, Z and TZ can be omitted. For example Q235-AF stands for Class A boiling steel.
Deoxygenation method
Q235A and Q235B steels each have three deoxidation methods, F, b and Z. Q235C steel is only killed steel, Q235D steel is only special killed steel. Boiling steel is a steel with incomplete deoxidation, and has poor plasticity and toughness. The welded structure made of this material is prone to cracks in the joint when subjected to dynamic loads. It is not suitable to work at low temperatures, and sometimes hardening occurs. In contrast, sedative steel is superior and homogeneous, with good ductility and toughness.
Q235 steel Chemical composition
| Standard | Steel Grade | Quality Grade | Chemical composition (%) | ||||
| C | Si | Mn | P | S | |||
| GB / 700 | Q235 | Q235A | ≤0.22 | ≤0.35 | ≤1.40 | ≤0.045 | ≤0.050 |
| Q235B | ≤0.20 | ≤0.35 | ≤1.40 | ≤0.045 | ≤0.045 | ||
| Q235C | ≤0.17 | ≤0.35 | ≤1.40 | ≤0.040 | ≤0.040 | ||
| Q235D | ≤0.17 | ≤0.35 | ≤1.40 | ≤0.035 | ≤0.035 | ||
Q235 steel Mechanical properties
| Standard | Steel Grade | Quality Grade | Yield Strength(MPa), Thickness or Dia(d) mm | Tensile Strength(MPa) | ||||
| D≤16 | 16＜d≤40 | 40＜d≤100 | 100＜d≤150 | 150＜d≤200 | d≤100 | |||
| GB / 700 | Q235 |
Q235A Q235B Q235C Q235D |
235 | 225 | 215 | 195 | 185 | 370~500 |
Q235 steel Minimum Elongation
| Standard | Steel Grade | Elongation(≥%), Thickness or Dia(d) mm | ||||
| d＜40 | 40＜d≤60 | 60＜d≤100 | 100＜d≤150 | 150＜d≤200 | ||
| GB / 700 | Q235 | 26 | 25 | 24 | 22 | 21 |
Q235 steel Minimum Charpy Impact
The different grades of Q235A, Q235B, Q235C, and Q235D represent mainly different impact temperatures. A means no impact, B is above 20 degrees, C is above 0 degrees, and D-20 is above. The difference between A and E refers to the difference in impact temperature in their performance. They are: Q235A grade, which is not required for impact toughness test; Q235B grade, which is used for normal temperature (20 ℃) impact toughness test; Q235C grade, which is used for 0 ℃ impact toughness test; Q235D grade, which is used for -20 ℃ impact toughness test. The impact toughness test uses Charpy V-notch test pieces. The impact toughness index is Akv. For the above-mentioned B, C, and D steels, under their respective different temperature requirements, Akv≥27J is required. The impact value varies at different impact temperatures.
| Standard | Steel Grade | Quality Grade | Charpy Impact(V notch) | |
| Temp ℃ | Impact energy(Longitudinal,≥J) | |||
| GB / 700 | Q235 | Q235A | - | - |
| Q235B | +20 | 27 | ||
| Q235C | 0 | |||
| Q235D | -20 |
Q235 Steel Bending Test Results
| Standard | Steel Grade | Cold Bending Test 180°（B=2a） | ||
| Sample Qrientation | Steel Dia.(d) of Curve Center | |||
| d≤60mm | 60mm＜d≤100mm | |||
| GB / 700 | Q235 | Vertical | a | 2a |
| Horizontal | 1.5a | 2.5a | ||
B=Sample Steel Width a=Sample Diameter or Thickness
Q235 Steel Equivalent grade
| Q235 steel equivalent grades | |||||||||||||
| China | US | Germany | Britain (UK) | Japan | France | ISO | |||||||
| Standard | Grade | Standard | Grade | Standard | Grade (Steel Number) | Standard | Grade (Steel Number) | Standard | Grade | Standard | Grade (Steel Number) | Standard | Grade |
| GB/T 700 | Q235A |
ASTM A36/A36M; ASTM A283/A283M |
A36 steel; Grade D |
BS 970 Prat 1 | 080A15 |
JIS G 3101; JIS G 3106 |
SS400; SM400A |
||||||
| GB/T 700 | Q235B |
ASTM A36; ASTM A283/A283M |
A36; Grade D |
DIN EN 10025-2 | S235JR (1.0038) | BS EN 10025-2 |
S235JR (1.0038) |
JIS G3101; JIS G3106 |
SS400; SM400A |
NF EN 10025-2 | S235JR (1.0038) | ||
| GB/T 700 | Q235C |
ASTM A36; ASTM A283/A283M; ASTM A573/A573M |
A36; Grade D; Grade 58 |
DIN EN 10025-2 | S235J0 (1.0114) | BS EN 10025-2 | S235J0 (1.0114) | JIS G3106 |
SM400A, SM400B |
NF EN 10025-2 | S235J0 (1.0114) | ISO 630-2 | S235B |
| GB/T 700 | Q235D |
ASTM A36; ASTM A283M |
A36; Grade D |
DIN EN 10025-2 | S235J0 (1.0114); S235J2 (1.0117) | BS EN 10025-2 | S235J0 (1.0114); S235J2 (1.0117) | JIS G3106 | SM400A | NF EN 10025-2 | S235J0 (1.0114); S235J2 (1.0117) | ISO 630-2 |
S235B, S235C |
Q235 die steel quenching
The quenching temperature is 950 ° C, the salt bath furnace is heated, and the 10% NaCl brine is cooled and quenched.
Application of Q235 steel
Q235 steel is widely used because of its low carbon content, good comprehensive properties, and good combination of strength, plasticity, and welding properties.
1. Q235 steel is widely used in construction and engineering structures. It is used to make steel bars or to build factory buildings, high-voltage transmission towers, bridges, vehicles, boilers, containers, ships, etc., and is also used in large quantities as mechanical parts with less demanding performance. Q235C, Q235D grade steel can also be used as some professional steel.
2. Q235 steel can be used for various mold handles and other insignificant mold parts.
3. Q235 steel is used as the punch material, and it is used directly after quenching without tempering. The hardness is 36 ~ 40HRC, which solves the phenomenon that the punch is broken in use.
