1. What is Q235 material?
Q235 is carbon structural steel in the Chinese national standard GB/T 700-2006. "Q" represents yield strength, and "235" indicates a yield strength ≥235MPa (thickness ≤16mm).
2. What was the old name for Q235?
The old name was A3 steel, which is the most widely used plain carbon steel in China.
3. What are the different quality grades of Q235?
It is divided into four grades: Q235A, B, C, and D. Impurities (S, P) decrease progressively with each grade, and low-temperature toughness increases progressively.
4. What are the main differences between Q235A and Q235B?
A: No impact test, C≤0.22%, S≤0.050%
B: Impact energy at 20℃ ≥27J, C≤0.20%, S≤0.045%
5. What are the applicable scenarios for Q235C and D? C: 0℃ impact, used in cryogenic/critical structures
D: -20℃ impact, used in extremely cold regions/pressure vessel foundation components