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Beam on Pd-D-Li Target Fusor

Posted: Wed Oct 24, 2018 3:07 pm
by Harald_Consul
Based on the previous "Beam on Solid State Fusor" design I have worked out a new more sophicticated design, now. It is similar, but the remarkable significant diffence is, that the target, which gets bombarded with deuterium ions, is out Palladium-Lithium alloy now.

Small alloy test charges are usually manufacured under labaratory conditions using a high-frequency induction heater . To manufacture a Pd-Li alloy you have to use additional flux, that covers up the Li-material, before you can melt it. As Lithium is a combustible light-metal it would start burning in the air, otherwise.

With the modification I get the following low budget design for an "Beam on Pd-D-Li Target Fusor":
  • Manufacturing an Palladium-Lithium electrode like mentioned above
  • Take a television tube from a bigger old school TV / CRT Monitor
  • Let the vacuum out
  • Cut a round! "service whole" into the television tube using a glas cutter (cornered holes will make the glass crack under vacuum)
  • Manufacturing an electrolytical cell, that will be filled with D2O, that has a prolonged electrode out of Pd-Li sheet on that side, where the deuterium is generated
  • The whole electrolytical cell is placed into the television tube
  • The televisons tube's electron generation unit's polarization is reversed and the voltage is increased, so that it produces a ion beam instead of an electron beam, now, when there is plasma in the tube
  • The prolonged Pd-Li-electrode is positioned at the Zero-beam position of the television tube
  • The tube's beam generation units and the electrolytical cell get powered; the electrolytical cell starts to produce deuterium, that gets stored as palladium-deuterium-ligand within in the electrode
  • The television tube is set under vaccuum. Due to the vaccum, some of the deuterium in the palladium electrode evaporades into the tube. A deuterium plasma is generated in the tube. From the deuterium plasma the tube's beam unit starts to produce a deuterium-ion beam.
  • Thus, the palladium-lithium-deuterid-ligand in the prolonged electrode gets bombarded with deuterium-ions
  • The Lithium in the Pd-Li electrode gets fissioned into tritium and helium
  • The bombardment of the tritium with deuterium ions startes a D-T fusion process
Remarks
From my point of view, this deuterium-tritium fusion process is not too dangerous, because
  • No direct toxic tritium gas is required,
  • most of the tritium, that is generated from lithium fission, gets bound to the palladium electrode (as deuterium and simple hydrogen do)
  • the tritium remains within a sealed (television) vacuum tube
  • additonally the whole gadgetry will be build within a fume cupboard to make sure no tritium gets to room air

Re: Beam on Pd-D-Li Target Fusor

Posted: Fri Oct 26, 2018 1:56 pm
by Harald_Consul
As there are no feedbacks to the design till 2 days now, I want to disclose the ideas behind it.

Supposed advantages: Supposed weaknesses, problems and dangers:
  • The reverse of the polarization of the television-tube's "cathode"-ray unit may not be suitable or not powerful enough to accelerate deuterium-ions to 2 keV or even 4keV
  • An experimental vacuum chamber, that already posses a "service hole" may be much more handy
  • The setup requires a tritium neutralisation concept and a fume cupboard. Although tritium is only a beta-emitter, the inhalation of tritium gas can cause serios bioaccumulation. However, a radiotoxic substance can be handled in laboratory more easily than a chemotoxic substance, because it can always be easiliy detected (using a Geiger counter).
  • The risk of producing a uncontrolled self-sustaining fusion reaction is estimated low, as the necessary activation energies of the nuclear fusion reaction are high. Especially, a chain reaction reaction does not seem possible, as far the target is small (e.g. 0.1 g) and the activation is not accomplished by a big simultanous "bang".

Re: Beam on Pd-D-Li Target Fusor

Posted: Tue Oct 30, 2018 12:01 am
by ian_krase
How are you ionizing the gas? While it probably can be done, electron guns are not made for functioning as ion guns.

Re: Beam on Pd-D-Li Target Fusor

Posted: Wed Oct 31, 2018 11:14 am
by Harald_Consul
Harald_Consul wrote: Wed Oct 24, 2018 3:07 pm
  • The television tube is set under vaccuum. Due to the vaccum, some of the deuterium in the palladium electrode evaporades into the tube. A deuterium plasma is generated in the tube. From the deuterium plasma the tube's beam unit starts to produce a deuterium-ion beam.
You are absolutely right. Only vacuum does not make a plasma, automatically. However, a full plasma is not required. Some ionized deterium ions next to reversed polarity "cathode ray" unit will be enough.

Any suggestions, how to best/ easierst create the deuterium ionization next to the reversed polarity "cathode ray"unit?

However, my current main problem is, I simply do not find a big demountable "cathode ray" tube.

Re: Beam on Pd-D-Li Target Fusor

Posted: Wed Dec 26, 2018 11:43 am
by vince_Darmancier
i"ve tried various oscilloscope tube as they produce a single beam (not 3 like a color TV)
it`s also easier to cut the glass around the cathode area and its possible to find old cheap oscilloscope
you may even be able to use the flyback transformer.
Given a good vacuum pump, seal etc.. you can even adjust the ion beam direction !

Re: Beam on Pd-D-Li Target Fusor

Posted: Wed Dec 26, 2018 1:54 pm
by John Futter
Unless you have used Simion or similar what makes you think that a set of lenses designed for electrons would work for protons or dueterons .
The proton is 1837 times heavier than the electron dueterons even heavier

Re: Beam on Pd-D-Li Target Fusor

Posted: Wed Dec 26, 2018 2:06 pm
by Harald_Consul
Thanks for the oscilloscope tip, Vince! How did you cut the tube exactly?

John, ion beam distraction by electric field is not required, here. I wanted to use the null-posiition of the beam. You might be right this way, that the maximum ion acceleration by the default voltage of the scope might be to low. However a higher voltage might be possible, depending on the tube.

Re: Beam on Pd-D-Li Target Fusor

Posted: Wed Dec 26, 2018 2:20 pm
by vince_Darmancier
that is true John but i did not think Harald wanted to used them as a tight focused beam.. but all the connections are already there for higher or lower voltage or whatever needed...
i have a friend who own a shop and works on glass as a professional , he was the one who cut the tube, attach vacuum connectors and cured the glass etc.. He might have simply used a glass cutter ...

Re: Beam on Pd-D-Li Target Fusor

Posted: Wed Dec 26, 2018 2:36 pm
by Harald_Consul
Would your friend manufacture a modified osci tube for me too? Could you PM his contact dates?

Re: Beam on Pd-D-Li Target Fusor

Posted: Wed Dec 26, 2018 3:16 pm
by vince_Darmancier
i guess he could ...he has done many custom glass work for me over the years...you could deal with him directly not sure about shipping tho
Superior glass Blowing (734) 482-8744 just call and explain what you need if he is not too busy ..

Re: Beam on Pd-D-Li Target Fusor

Posted: Thu Dec 27, 2018 1:08 am
by ian_krase
Personally, I would avoid messing around with a cathode ray tube and just build up an ion source from normal lab-bench vacuum components.

Also worth noting is that electron beams are not really efficient for bulk ionization of gas, and they have drawbacks. The coating on the cathode may not survive exposure to air even when cold and is easily poisoned by various materials.

I would use a kanal or magnetron style of ion source.

Re: Beam on Pd-D-Li Target Fusor

Posted: Thu Dec 27, 2018 9:05 am
by Dennis P Brown
There are many posts and designs for true deuterium ion guns here in this forum to search out. Also, focusing of the beam, while not really needed for short systems, is extremely easy using a simple electro-magnet (wound copper wire coil) or even a simple ring magnet mounted onto a glass tube (the glass tube being your vacuum accelerating path - gun at one end, target at the other.)

These designs require high vacuum to work (10^-6 torr) - so a diffusion pump with a trap or turbo is essential - ions do not travel far otherwise.

Another issue is the accelerating voltage. Most people use a positive 50 - 100 kV power supply to repeal/drive the ions (and a 5-15 kV negative supply to ionize the gas.) As for voltage the higher the better to get good rates of fusion; also, power supply current matters since that will ultimately determine your ion current.

These designs can be fierce x-ray sources so one needs to shield these devices carefully and take precautions.

As someone who built such a unit they are not too difficult to build in theory but in practice, can get complex fast. I abandoned mine at its test stage for a fusor after building a complete unit - my van de graaf failed and the 75 kV supply I built was far too dangerous to operate in the open - hind site. But it was fun building that monster.

A titanium target is just as good as a Pd one since both can be used to hold deuterium.

The amount of any tritium created in any fusor reaction by any system someone can build is so trivial and irrelevant that it will have essentially zero probability of reacting in any manner. As for health dangers from tritium even from a high end fusor - that is zero.

That all said, building a simple ion gun (low voltage ionizer system) isn't difficult and can be useful as an exercise in vacuum work and learning about moderate voltage power supplies (1 - 5 kV.) But don't expect any fusion at all relative to a target if you use any such low voltage system.