1. Specified grade
| Grade mark |
Description |
Equivalent JIS mark |
| CR2, 400, 490 |
A |
Atmospheric corrosion-resistant steel plate for painting |
6mm≤ thickness≤ 200mm |
JIS G3114 SMA400, 490AP
JIS G3114 SMA400, 490BP
JIS G3114 SMA400, 490CP |
| B |
| C |
6mm≤ thickness≤ 100mm |
| CR2, 570 |
JIS G3114 SMA570P |
| CR2M-400, 490 |
A |
Atmospheric corrosion-resistant steel
plate for bare use or rust stabilizing treatment |
6mm≤ thickness≤ 200mm |
JIS G3114 SMA400, 490AW
JIS G3114 SMA400, 490BW
JIS G3114 SMA400, 490CW |
| B |
| C |
6mm≤ thickness≤ 100mm |
| CR2M, 570 |
JIS G3114 SMA570W |
| CR2R, H |
Highly atmospheric corrosion-resistant steel plate |
6mm≤ thickness≤ 19mm |
JIS G3125 SPA-H |
2. Reduced pre-heating type steel
Reduced pre-heating type steels are aimed at reducing pre-heating to keep weld crack susceptible structure (PCM) as low as possible. They are expressed with -EX suffixed to grade or pre-heating marks. Applicable grades are CR2-490, CR2-570, and CR2M-570. As for weld crack susceptible structure (PCM), please consult us.
3. Standardized value
| Grade mark |
Chemical composition (%) |
| C |
Si |
Mn |
P |
S |
Cu |
Ni |
Cr |
Mo |
Nb + V |
| 450 |
450 |
450 |
450 |
450 |
450 |
450 |
450 |
450 |
450 |
450 |
| CR2-400 |
≤ 0.18 |
≤ 0.35 |
≤ 1.40 |
≤ 0.035 |
≤ 0.035 |
0.20 - 0.60 |
≤ 0.65 |
0.20 - 0.65 |
- |
≤ 0.15 |
| CR2M-400 |
≤ 0.18 |
≤ 0.35 |
≤ 1.40 |
≤ 0.035 |
≤ 0.035 |
0.30 - 0.60 |
≤ 0.65 |
0.45 - 0.75 |
- |
≤ 0.15 |
| CR2-490 |
≤ 0.18 |
≤ 0.75 |
≤ 1.40 |
≤ 0.035 |
≤ 0.035 |
0.20 - 0.70 |
≤ 0.65 |
0.30 - 1.20 |
- |
≤ 0.15 |
| CR2M-490 |
≤ 0.18 |
≤ 0.75 |
≤ 1.40 |
≤ 0.035 |
≤ 0.035 |
0.30 - 0.70 |
≤ 0.65 |
0.45 - 1.20 |
- |
≤ 0.15 |
| CR2-570 |
≤ 0.18 |
≤ 0.75 |
≤ 1.40 |
≤ 0.035 |
≤ 0.035 |
0.20 - 0.70 |
≤ 0.65 |
0.30 - 1.20 |
≤ 0.20 |
≤ 0.15 |
| CR2M-570 |
≤ 0.18 |
≤ 0.75 |
≤ 1.40 |
≤ 0.035 |
≤ 0.035 |
0.30 - 0.70 |
≤ 0.65 |
0.45 - 1.20 |
≤ 0.20 |
≤ 0.15 |
| CR2R-H |
≤ 0.12 |
0.25 - 0.75 |
0.20 - 0.50 |
0.070 - 0.150 |
≤ 0.035 |
0.25 - 0.55 |
≤ 0.45 |
0.30 - 1.00 |
- |
- |
| Note 1: |
In any case where Ti, Zr, etc., which are effective for atmospheric corrosion resistance, are added, the total added elements such as Mo, Nb, V, Ti, and Zr shall be not more than 0.15%.
|
| 2: |
The weld crack susceptibility composition (PCM) and carbon equivalent (Ceq) of steel plates made by the thermo-mechanical control process are determined by agreement.
|
4. Mechanical properties
| Grade mark |
Tensile test |
Bending test |
| Yield point or proof stress (N/mm2) |
Tensile strength (N/mm2) |
Elongation |
| Plate thickness (mm) |
Plate thickness (mm) |
Test piece |
% |
Bending angle |
Inner radius |
| 6 ≤ t ≤ 16 |
16 ≤ t ≤ 40 |
40 ≤ t |
CR2-400
CR2M-400 |
245 ≤ |
235 ≤ |
215 ≤ |
400-510 |
6 ≤ t ≤ 16 |
1A |
19 ≤ |
180 º |
|
| 16 ≤ t |
1A |
22≤ |
| 40 ≤ t |
4 |
24 ≤ |
CR2-490
CR2M-490 |
365 ≤ |
355 ≤ |
335 ≤ |
490-610 |
6 ≤ t ≤ 16 |
1A |
16 ≤ |
|
| 16 ≤ t |
1A |
19 ≤ |
| 40 ≤ t |
4 |
21 ≤ |
CR2-570
CR2M-570 |
460 ≤ |
450 ≤ |
430 ≤ |
570-720 |
6 ≤ t ≤ 16 |
5 |
19 ≤ |
|
| 16 ≤ t |
5 |
26 ≤ |
| 40 ≤ t |
4 |
20 ≤ |
| CR2R-H |
345 ≤ |
- |
480 ≤ |
- |
5 |
22 ≤ |
180 º |
|
*Bending test is omitted unless required.
|
