The tantalum furnace has a heater tube made from tantalum foil, and two radiation shields within the vacuum chamber. It is water cooled.
| T [K] | heater power [W] | U(prim) [V] | I(prim) [A] | I(2nd) [A] | T(wall) [K] | cooling rate [K/min] |
|---|---|---|---|---|---|---|
| 1400 | 2730 | 152 | 17.8 | 4 x 70.4 | 350 | |
| 1300 | 2060 | 130 | 15.8 | 4 x 57 | 330 | |
| 1200 | 1500 | 110 | 14.1 | 4 x 46 | 320 | |
| 1100 | 1050 | 88 | 12.5 | 4 x 37.5 | 310 | |
| 1000 | 730 | 70 | 10.8 | 4 x 29.8 | 303 | > 50 |
| 900 | 480 | 58 | 9.0 | 4 x 23.3 | 298 | 50 |
| 800 | 325 | 50 | 7.5 | 4 x 18.0 | 293 | 30 |
| 700 | 195 | 291 | 17 | |||
| 600 | 120 | 290 | 10 | |||
| 500 | 74 | 289 | 4 | |||
| 450 | 53 | 289 | 3 | |||
| 400 | 38 | 4 x 4.7 | 289 | 1.5 |
Temperature of the connections at 1400 K: 90-100 deg Celsius
The furnace must not be vented above 373 K. Cool down from 1400 K takes about 90 min, from 500 K still 60 min!
Sketch of tantalum furnace (not to scale)
Connection of Furnace:
