优质碳素结构钢Quality Carbon Structural Steels
| Grade | Diameter（mm） | Standard | C | Si | Mn | P | S | Ni | Cu | Cr |
| 20 | ￠18-60 ￠50-130 ￠160-230 |
GB/T |
0.17-0.23 | 0.17-0.37 | 0.35-0.65 | ≤0.035 | ≤0.035 | ≤0.30 | ≤0.25 | ≤0.25 |
| 45 | 0.42-0.50 | 0.17-0.37 | 0.35-0.65 | ≤0.035 | ≤0.035 | ≤0.30 | ≤0.25 | ≤0.25 |
| Grade | Diameter（mm▓█】） | Standard | C | Si | Mn | P | S | Ni | Cu | Cr |
| 10 | ￠50-130 ￠160-230 |
GB/T |
0.07-0.13 | 0.17-0.37 | 0.35-0.65 | ≤0.035 | ≤0.035 | ≤0.30 | ≤0.25 | ≤0.15 |
| 20 | 0.17-0.23 | 0.17-0.37 | 0.35-0.65 | ≤0.035 | ≤0.035 | ≤0.30 | ≤0.25 | ≤0.25 |
| Grade | Diameter（mm） | Standard | C | Si | Mn | P | S | Ni | Cu | Cr | Mo |
| 40Cr | ￠18-60 | GB/T | 0.37-0.44 | 0.17-0.37 | 0.50-0.80 | ≤0.035 | ≤0.035 | ≤0.30 | ≤0.30 | 0.80-1.10 | ≤0.15 |
| Grade | Diameter（mm▓█】） | Standard | C | Si | Mn | P | S | Ni | Cu | Cr | O | Mo |
| GCr15 | ￠18-60 | GB/T | 0.95-1.05 | 0.15-0.35 | 0.25-0.45 | ≤0.025 | ≤0.025 | ≤0.30 | ≤0.30 | 1.40-1.65 | 12*10ˉ6 | ≤0.10 |
| GCr4 | ￠18-60 | GB/T | 0.95-1.05 | 0.15-0.30 | 0.15-0.30 | ≤0.025 | ≤0.020 | ≤0.25 | ≤0.20 | 0.35-0.50 | 12*10ˉ6 | ≤0.08 |
| GCr15SiMn | ￠18-60 | GB/T | 0.95-1.05 | 0.45-0.75 | 0.95-1.25 | ≤0.025 | ≤0.025 | ≤0.30 | ≤0.25 | 1.40-1.65 | 12*10ˉ6 | ≤0.10 |
| Grade | Diameter（mm） | Standard | C | Si | Mn | P | S | Ni | Cu | Cr | V | Ti | Mo |
| 20CrMnTi | ￠18-60 | GB/T | 0.17-0.23 | 0.17-0.37 | 0.80-1.10 | ≤0.035 | ≤0.035 | ≤0.30 | ≤0.30 | ≤1.00-1.30 | 0.04-0.10 | ≤0.15 | |
