30 9 月, 2026
Chinese Steel Grades Explained: Q195, Q235 and Q355
The Chinese carbon structural steel grades are defined by GB/T 700 and read simply: Q for qufu (yield), then the minimum yield strength in MPa. So Q195 is a 195 MPa grade, Q235 is 235 MPa and Q355 is 355 MPa. A trailing letter gives the quality class, which controls impact toughness and the sulphur and phosphorus limits.
The three grades side by side
| Chinese grade | ASTM | EN | JIS |
|---|---|---|---|
| Q195 GB/T 700 |
A36 (approx.) | S185 (EN 10025-2) | SS330 (JIS G3101) |
| Q235B GB/T 700 |
A36 / A283 Gr.C | S235JR (EN 10025-2) | SS400 (JIS G3101) |
| Q355B GB/T 1591 |
A572 Gr.50 / A992 | S355JR (EN 10025-2) | SM490 (JIS G3106) |
| Q215 GB/T 700 |
A283 Gr.C (approx.) | S235JR (approx.) | SS330 |
Q235B technical data
Chemical composition (ladle analysis, %)
| Element | Limit |
|---|---|
| C | ≤0.20 |
| Si | ≤0.35 |
| Mn | ≤1.40 |
| P | ≤0.045 |
| S | ≤0.045 |
Mechanical properties
| Property | Value |
|---|---|
| Yield strength (ReL) | ≥235 MPa |
| Tensile strength (Rm) | 370–500 MPa |
| Elongation (A) | ≥26% |
| Impact energy | +20 °C, ≥27 J |
Which grade to choose
| Requirement | Usual grade |
|---|---|
| Light fabrication, welded pipe, general forming | Q195 |
| General structural work, the workhorse grade | Q235B |
| Higher strength structures and thinner sections | Q355B |
| Low-temperature or certified service | A higher quality class, verified for the design temperature |
What to state in the enquiry
- The full designation including the quality class letter
- The product form and dimensions
- The certification and, if required, the impact test temperature
- The delivery term and destination port
Related reading
Frequently asked questions
What does Q mean in Chinese steel grades?
Q stands for qufu, meaning yield. The number after it is the minimum yield strength in MPa, so Q235 is a steel with a minimum yield strength of 235 MPa.
What is the difference between Q195, Q235 and Q355?
Mainly the minimum yield strength: 195, 235 and 355 MPa respectively. Q195 is soft and highly formable, Q235B is the general structural workhorse, and Q355B is used where higher strength allows lighter sections.
What is the equivalent of Q235B in other standards?
Our database maps Q235B to ASTM A36 or A283 Gr.C, EN S235JR and JIS SS400 as nearest equivalents. The certificate must still reference the standard your project requires.
Tell us the standard, grade, form and size you need and we will quote against it. See our steel product catalogue, how we inspect and certify each order, or request a quotation.