Comment by gaze
8 hours ago
There are NO alternatives. There's nothing else that stays liquid at 4 K and absolutely nothing else comes close.
8 hours ago
There are NO alternatives. There's nothing else that stays liquid at 4 K and absolutely nothing else comes close.
> There are NO alternatives.
We use a lot in our MR scanners.
The tech is changing and magnets are using far far less.
Super-conduction at higher temperatures has made progress too.
So while you are right that nothing else stays liquid at those temps, we won’t be needing nearly as much helium in radiology in the next few years.
The new generation use something like 700ml of helium, where the standard was hundreds of litres. https://magneticsmag.com/siemens-healthineers-gets-fda-clear...
The article itself spells out several alternatives to buying continuous amounts of Helium: high temperature semiconductors and zero boil-off systems that don't require a continual supply.
All these "we're going to run out" stories pretend that engineering cannot adapt to changing cost structures, which is just total nonsense.
Sure, there is nothing that can be directly substituted for how we use Helium today, but clearly we're using Helium inefficiently today and the answer is that once markets force us to change, we will find more efficient ways.
The article also points out several cases where this isn't possible