Zr, Mo, W and Ta determination in niobium alloys
The standard test method specifies Zr (Zirconium), Mo (Molybdenum), W (Tungsten) and Ta (Tantalum) determination in niobium alloys.
The sample preparation consists of fusing the sample batch with potassium pyrosulfate. The obtained fuse is grinded to the particle size of 71 micron.
Then the powder sample material is pressed into two pellets in a boron acid cup. Boron acid cup is pressed out with a shaped punch being at least 3 mm deep. Sample material is put into the cup and pressed with a flat punch into a pellet.
The pellet is put into the sample holder and then into a spectrometer. Analysis is carried out automatically according to the chosen program. The program can determine all elements (oxides) listed in the test method or some of those elements by choice.
The standard test method specifies element mass content determination in the ranges listed in the table:
| Element | Mass content range, % |
| Zr | 0,2 – 2,5 |
| Mo | 0,5–6,0 |
| W | 2,0 – 12,0 |
| Ta | 0,15 – 1,5 |