| 牌号 | W-1 | W-2 | W-4 |
|---|---|---|---|
| W(%) | ≥99.95 | ≥99.95 | ≥99.90 |
| Fe | ≤0.003 | ≤0.004 | ≤0.030 |
| Si | ≤0.002 | ≤0.002 | ≤0.005 |
| Ca | ≤0.002 | ≤0.002 | ≤0.005 |
| Al | ≤0.002 | ≤0.002 | ≤0.005 |
| Mg | ≤0.001 | ≤0.001 | ≤0.005 |
| Ni | ≤0.002 | ≤0.002 | ≤0.050 |
| Sb | ≤0.001 | ≤0.001 | ≤0.001 |
| As | ≤0.0015 | ≤0.002 | ≤0.002 |
| Sn | ≤0.0003 | ≤0.0005 | ≤0.001 |
| Bi | ≤0.0001 | ≤0.0001 | ≤0.0005 |
| Cu | ≤0.001 | ≤0.002 | ≤0.005 |
| Mo | ≤0.005 | ≤0.010 | ≤0.020 |
| O(%) | ≤0.003 | ≤0.005 | ≤0.007 |