TABLE 1. Chemical Requirements:
| Content, Max, Weight % | ||||
| Element | Grand: R04200 | Grand:R04210 | Grand:R04251 | Grand:R04261 |
| Unalloyed Niobium | Unalloyed Niobium | (Reactor grade niobium-1% Zirconium) | (Commercial grade niobium-1% Zirconium) | |
| C | 0.01 | 0.01 | 0.01 | 0.01 |
| O | 0.015 | 0.025 | 0.015 | 0.025 |
| N | 0.01 | 0.01 | 0.01 | 0.01 |
| H | 0.0015 | 0.0015 | 0.0015 | 0.0015 |
| Fe | 0.005 | 0.01 | 0.005 | 0.01 |
| Mo | 0.01 | 0.02 | 0.01 | 0.05 |
| Ta | 0.1 | 0.3 | 0.1 | 0.5 |
| Ni | 0.005 | 0.005 | 0.005 | 0.005 |
| Si | 0.005 | 0.005 | 0.005 | 0.005 |
| Ti | 0.02 | 0.03 | 0.02 | 0.03 |
| W | 0.03 | 0.05 | 0.03 | 0.05 |
| Zr | 0.02 | 0.02 | 0.8~1.2 | 0.8~1.2 |
| Nb | Remainder | Remainder | Remainder | Remainder |
TABLE 2.Mechanical Requirements:
| Grade(UNS) | Annealed | ||
| Tensile strength min, psi (MPa) | Yield strength min,psi (MPa)(2%) | Elongation min, % (1 inch gage length) | |
| R04200, R04210 | 18000 (125) | 10500 (73) | 15~20 |
| R04251, R04261 | 28000 (195) | 18000 (125) | 15~20 |
| R04220(RRR grade) | 14000 (95) | 7200 (50) | 30 |

