The main difference is that ASTM A709 Grade 36 is a U.S. standard with a minimum yield strength of 36,000 psi (36 ksi), while Q345q is a Chinese standard with a minimum yield strength of 345 MPa. Both are high-strength low-alloy steels used for bridges, but they have different standard specifications and strength levels, with Q345q having a higher minimum yield strength when converted to the same units.
Chemical composition % of the Product analysis of A709 Grade 36
|
Thick mm |
Structural steel |
Steel Plate |
Round Bar steel |
|||||
|
≤20 |
20～≤40 |
40～≤65 |
65～≤100 |
≤20 |
20～≤40 |
40～≤100 |
||
|
C,max,% |
0.25 |
0.25 |
0.25 |
0.25 |
0.27 |
0.26 |
0.27 |
0.28 |
|
Mn,% |
… |
… |
0.80-1.20 |
0.80-1.20 |
0.80-1.20 |
… |
0.60-0.90 |
0.60-0.90 |
|
P,max,% |
0.04 |
0.04 |
0.04 |
0.04 |
0.04 |
0.04 |
0.04 |
0.04 |
|
S,max,% |
0.05 |
0.05 |
0.05 |
0.05 |
0.05 |
0.05 |
0.05 |
0.05 |
|
Si |
0.40max |
0.40max |
0.40max |
0.15-0.40 |
0.15-0.40 |
0.40max |
0.40max |
0.40max |
|
Cu,min,% |
0.20 |
0.20 |
0.20 |
0.20 |
0.20 |
0.20 |
0.20 |
0.20 |
Mechanical properties of grade A709 Grade 36
|
Grade |
Thick |
Yield Min |
Tensile [MPa] |
Elongtation Min % |
reduction Min % |
HB |
|||
|
Steel Plate |
Structural steel |
||||||||
|
200mm |
50mm |
200mm |
50mm |
||||||
|
A709 36[250] |
≤100 |
250 |
400-550 |
20 |
23 |
20 |
21 |
|
|
|
|
250 |
400min |
|
|
20 |
19 |
|
||
Q345R Steel Plate Chemical Composition:
| Steel Grade | C % | Si % | Mn % | Cu % | Ni % | Cr% | Mo % | V % | Ti % | Alt % | P % | S % | Nb |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Q345R | 0.20 | 0.55 | 1.2-1.7 | 0.30 | 0.30 | 0.30 | 0.08 | 0.050 | 0.030 | 0.020 | 0.025 | 0.010 | 0.050 |
Q345R Steel Plate Mechanical Property:
| Steel Grade | Thickness(mm) | Min Yield | Tensile | Elongation | Min Impact Energy | |
|---|---|---|---|---|---|---|
| Degree | Min J | |||||
| Q345R | 3-16 | 345Mpa | 510-640 Mpa | 21% | 0 | 41J |
| 16-36 | 325Mpa | 500-630 Mpa | 21% | 0 | 41J | |
| 36-60 | 315 Mpa | 490-620 Mpa | 21% | 0 | 41J | |
| 60-100 | 305 Mpa | 490-620 Mpa | 20% | 0 | 41J | |
| 100-150 | 285 Mpa | 480-610 Mpa | 20% | 0 | 41J | |
| 150-250 | 265 Mpa | 470-600 Mpa | 20% | 0 | 41J | |
