Chemical composition:
| Main and minor components | Min.content(%) | ASTM B365 |
| Ta | 99.95 | balance |
| Impurities | Max.values (μg/g) | Max.values (μg/g) |
| Fe | 100 | 100 |
| Mo | 100 | 200 |
| Nb | 400 | 1000 |
| Ni | 50 | 100 |
| Si | 50 | 50 |
| Ti | 50 | 100 |
| W | 100 | 500 |
| C | 30 | 200 |
| H | 15 | 15 |
| N | 50 | 100 |
| O | 100 | 250 |
| Cd | 10 | - |
| Hg | 1 | - |
| Pb | 10 | - |
Diameter and tolerance
| Diameter (mm) | Diameter tolerance (mm) |
| Ground | |
| 3.00-15.9 | ±0.05 |
| 16.0-24.9 | ±0.10 |
| 25.0-34.9 | ±0.25 |
| 35.0-39.9 | ±0.40 |
| 40.0-50.0 | ±0.80 |
| Cleaned | |
| 3.00-4.74 | ±0.076 |
| 4.75-9.51 | ±0.102 |
| 9.52-12.69 | ±0.127 |
| 12.70-15.87 | ±0.178 |
| 15.88-19.04 | ±0.203 |
| 19.05-25.39 | ±0.254 |
| 25.40-38.09 | ±0.381 |
| 38.10-50.79 | ±0.508 |
| 50.80-63.49 | ±0.762 |
| 63.50-120.0 | ±1.50 |
| Turned | |
| 30.0-49.9 | ±0.30 |
| 50.0-120.0 | ±0.40 |
Length and straightness:
| Diameter (mm) | Production length (mm) | Stiraightness/Meter (mm) | |
| Cleaned | Ground/turned | ||
| 3.00-9.90 | ＞500 | ＜2.5 | ＜2.0 |
| 10.0-120.0 | ＞300 | ＜2.5 | ＜1.5 |
Length tolerance:
| Nominal length (mm) | 6-30 | 30-120 | 120-400 | 400-1000 | 1000-2000 | ＞2000 |
| Length tolerance(mm) | ±1.0 | ±1.5 | ±2.5 | ±4.0 | ±6.0 | ±8.0 |
Density: ≥16.6g/cm³
Nondestructive testing: For diameters＞15.00 mm:100% ultrasonic testing; For diameters of 0.50-50.0mm: Eddy curent tests on rods with ground surface.
| Diameter(mm) | Tensile strength(MPa) | 0.2% Yield Strength (MPa) | Elongation(%) |
| 3.00-3.19 | ≥207 | - | ≥20 |
| 3.20-63.5 | ≥172 | ≥103 | ≥25 |
Surface condition:
| Surface | Pickled | Ground | Turned |
| φ3.0-165.0mm | φ3.0-50.00mm | φ≥30.00mm | |
| Roughness | Diameter (mm) | Ra (μm) Ground | Ra (μm) Turned |
| 3.0-50.0 | ≤1.20 | - | |
| ≥30.0 | - | ≤3.2 |