グレードと化学成分（％）
| 学年 | C | Mn | P≤ | S≤ | Si | Cr | Mo |
| 1008 | ≤0.10 | 0.30～0.50 | 0.040 | 0.050 | - | - | - |
| 1010 | 0.08～0.13 | 0.30～0.60 | 0.040 | 0.050 | - | - | - |
| 1018 | 0.15～0.20 | 0.60～0.90 | 0.040 | 0.050 | - | - | - |
| 1020 | 0.18～0.23 | 0.30～0.60 | 0.040 | 0.050 | - | - | - |
| 1025 | 0.22～0.28 | 0.30～0.60 | 0.040 | 0.050 | - | - | - |
| 1026 | 0.22～0.28 | 0.60～0.90 | 0.040 | 0.050 | - | - | - |
| 4130 | 0.28～0.33 | 0.40～0.60 | 0.040 | 0.040 | 0.15～0.35 | 0.80～1.10 | 0.15～0.25 |
| 4140 | 0.38～0.43 | 0.75～1.00 | 0.040 | 0.040 | 0.15～0.35 | 0.80～1.10 | 0.15～0.35 |
機械的性質：
|
|
| MPa |
|
|
| 1020 | CW | ≥414 | ≥483 | 5%以上 |
|
| SR | ≥345 | ≥448 | ≥10% |
|
| A | ≥193 | ≥331 | ≥30% |
|
| N | ≥234 | ≥379 | ≥22% |
| 1025 | CW | ≥448 | ≥517 | 5%以上 |
|
| SR | ≥379 | ≥483 | 8%以上 |
|
| A | ≥207 | ≥365 | ≥25% |
|
| N | ≥248 | ≥379 | ≥22% |
| 4130 | SR | ≥586 | ≥724 | ≥10% |
|
| A | ≥379 | ≥517 | ≥30% |
|
| N | ≥414 | ≥621 | ≧20% |
| 4140 | SR | ≥689 | ≥855 | ≥10% |
|
| A | ≥414 | ≥552 | ≥25% |
|
| N | ≥621 | ≥855 | ≧20% |
