Hydrogen even diffuses through (and into) metal - seems not doable, not cheaply and without maintenance at least.

Helium atoms are actually smaller than hydrogen atoms, and much smaller than hydrogen mollecules.

While that is true, there are metals through which hydrogen can diffuse faster than helium, because the hydrogen molecules dissociate and ionize when entering the metal and the hydrogen ions diffuse through the metal individually.

Wouldn't be a fire risk because there's no oxygen available. But hydrogen is chemically reactive and over time it could corrode or weaken the materials inside the HDD.

That's not the main problem. The main problem is hydrogen is fucking painful to contain.

Not as painful as helium. Bigger atom but it leaks more.

Ah, truth. Brain fart.

ASME Boiler and Pressure Vessel Section V

Helium leak detection sensitivity is 3 orders of magnitude higher.

Memory is fallible, but the code doesn't lie.

Oh, the huge HDD.

> Hydrogen would also be .. interesting ...

Why?

It's used in power station generators. Why would a hard disk be interesting?

https://en.wikipedia.org/wiki/Hydrogen-cooled_turbo_generato...

Cause exploding hard drives are metal AF

It won't explode until it's mixed with oxygen.

Hold my beer.

The small amount contained in the HDD would a minimal risk.

Larger amounts handled in the manufacturing process, OTOH...

I'm curious how the shaft seals for generators manage to seal the hydrogen. Perhaps the hydrogen is contained within the the generator and not exposed to the seals, though I thought one of the reasons for its use (along with cooling) was reduced windage losses.