Center for Emerging Energy Sciences
Advanced Materials Fabrication & Diagnostics:
Absorbed atmospheric 4He in various technical materials
It is essential to measure the amount of helium gas that is stored within various technical solids that are used in the construction of LENR devices, if helium is to be used as a quantitative indicator of nuclear activity. The temperatures at which these materials outgas He, and/or become porous to the 5.2 ppm level of 4He within the atmosphere, must be understood as well. This knowledge of materials is also essential in order to know what fraction of helium is recovered from the bulk material that has produced the helium isotope(s), so that the actual production rate may be determined from subsequent measurements.
A shortened data table is included below. A detailed technical report on helium outgassing from materials is attached here.
Total helium amount outgassed and release temperature of out-gassing from different materials.:
|
Sample |
Weight / Size |
Maximum Baking Temerature (°C) |
4He Outgassing (picomoles) |
4He Outgassing (picomoles / gram) |
Outgassing Temperature (°C) and Comments |
| Blank Palladium plate | --- | 600 | 2.7 | --- | --- |
| PTFE | 1.25 g | 450 | 281 | 224.8 | --- |
| Large PTFE Tube | 1.009 g | 600 | 50 | 49.55 | above melting temperature of PTFE |
| Small PTFE Tube | 1.006 g | 500 | 87 | 86.48 | above melting temperature of PTFE |
| AWG PTFE Tube | 1.006 g | 500 | 48 | 47.71 | above melting temperature of PTFE |
| MACOR as delivered | 13 g | 600 | 280 | 21.54 | 600 |
| MACOR Prebaked, 2 days in atmosphere | 13 g | 600 | 110 | 8.46 | --- |
| MACOR Soaked in 4He for 8 hours (25 °C) | 13 g | Room Temperature | 5400 | 415.38 | Room Temperature |
| MACOR Soaked in 4He for 8 hours (600 °C) | 13 g | 600 | 3800 | 292.31 | --- |
| CF Cell Diffusion Test | --- | Room Temperature | 500 | --- | Room Temperature |
| 4He-Soaked CF Cell 2 | --- | Room Temperature | 290000 | --- | Room Temperature |
| (4) 3" Teflon Stripes, McMaster | 7.061 g | 600 | 7100 | 1005.5 |
380 Temperature at which outgassing first observed from signal increase |
| (4) Nylon Nuts | 0.191 g | 400 | 1.6 | 8.38 | No sign of outgassing |
| Nylon Screws | 0.184 g | 400 | 3.6 | 19.57 | No sign of outgassing |
| PTFE TWTT-22C | 0.66 g | 550 | 9.9 | 15 |
360 Temperature at which outgassing first observed from signal increase |
| PTFE Plate Washer | 3.857 g | 550 | 19 | 4.93 |
360 Temperature at which outgassing first observed from signal increase |
| Nylon Nuts | 0.807 g | 400 | 0.8 | 0.99 | No sign of outgassing |
| Nylon Screws | 0.921 g | 400 | 0.44 | 0.48 | No sign of outgassing |
| Pd #2 wire 0.009" Diameter 12" | 0.15 g | 21.3 | 142 | evaporation | |
| Pd #1 wire 0.009" Diameter 12" | 0.15 g | 3.83 | 25.5 | evaporation | |
| SS304 Capillary | 0.32 g | 19.4 | 60.6 | evaporation |
· PTFE melting temperature: 327 °C
· Nylon melting temperature: 220 °C; decomposition temperature: 307 °C
Department of Physics and Astronomy
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