by matricaria on 8/31/24, 7:46 AM with 58 comments
by femto on 9/1/24, 8:39 AM
TIG temperature can easily reach 3000C (close enough to 3000K) [1], more than the boiling point of beryllium. The temperature of the metal slug would rise until it reaches thermal equilibrium through heat loss, the energy loss likely being due to the vapourisation of the element with the lowest boiling point: beryllium.
That smoke was probably beryllium vapour.
I'm no expert, but I would assume the beryllium vapour would not have made it out of the apparatus. By luck, it would have condensed either before reaching the HEPA filter or on its way through the HEPA filter, even though the HEPA filter was not designed to stop a vapour. Nile Red also had the sense to use a fume cupboard. Despite this, the inside of the apparatus could well have been coated with friable condensed beryllium, which would probably not have been flushed by the argon. If doing this, I'd take additional precautions against condensing beryllium vapour containing the equipment (I don't know what they might be).
Maybe it's a case of controlling arc temperature to keep it below the boiling point of beryllium? Maybe a small amount of impurity with a lower boiling point can be added to the mix, so it boils off first and avoids the beryllium boiling? This might also prevent loss of beryllium from altering the composition of the glass?
How would the pros handle this risk?
I gather there are similar issues with the refining of silicon, in which silicon vapour can cause silicosis.
Element Melt Boil
Beryllium 1560K 2742K
Copper 1357K 2835K
Nickel 1728K 3003K
Titanium 1491K 3560K
Zirconium 2125K 4650K
by JKCalhoun on 9/1/24, 2:41 AM
I recall too a pair of angled plinths and the steel balls would appear from an opening in the display, drop and bounce from one plinth to the other before exiting (repeat).
No amount of googling has helped shed any light as to "What that was". Perhaps this metallic glass.
(Also recall a computer that you could play Tic-Tac-Toe against. The input was a more or less a telephone keypad, the display large neon X's and O's. Seven year old me, or thereabouts, was fascinated to read that the computer had never yet lost.)
by gcanyon on 9/1/24, 1:23 AM
by rowanG077 on 9/1/24, 3:07 AM
by chii on 9/1/24, 6:12 AM
I wonder what else could the forge be used for in future videos?
by somat on 8/31/24, 8:18 AM
What happens if you just use glass for the bouncing surface? I was reading about the materials and I am not sure what property contributes to it's bounciness, but I think it is tensile strength(but it may be surface hardness). and regular glass has a slightly lower tensile strength than these amorphous metallic structures, fused quartz has a higher tensile strength, and I was unable to find out what tempered glass is, but I suspect tempered glass would tend to shatter if a small hard ball was bounced off it. Anyway, I was unable to form a good hypothesis as to what would happen, but I did find that mcmaster-carr sells fused quartz disks if anyone wants to try.
https://www.mcmaster.com/products/glass-discs/ultra-high-tem...
by mikewarot on 9/1/24, 2:29 PM
A VERY flat surface might greatly increase the bounce.
A surface coating of BAM[2] might also help, by increasing the hardness, and lubricity.
I think there's a lot of room to go in increasing the hang time of the bouncing bearing.
[1] https://en.wikipedia.org/wiki/Electrochemical_grinding
[2] https://en.wikipedia.org/wiki/Aluminium_magnesium_boride
by perdomon on 9/1/24, 2:51 AM
by arendtio on 9/1/24, 10:29 AM
by emilfihlman on 9/1/24, 12:26 PM