Potential Massive Improvement in Superconductors

KitemanSA · Post by **KitemanSA** » Fri Jan 30, 2009 3:42 pm

imaginatium wrote:So what's the most cost effective superconductor, that can be LN2 cooled?

American Superconductor, one premier supplier of HTS, discusses magnets using their YBCO 2nd generation wire running at 20-40K, even though YBCO is a 98K+ SC.

imaginatium · Post by **imaginatium** » Fri Jan 30, 2009 6:47 pm

MSimon wrote:
imaginatium wrote:
MSimon wrote:My BOE calculations say that to get reasonable fields - .45T continuous - you have to go to LN2.

It is cheap for one shot experiments and can be reliquefied for continuous operation. Or just operated total loss for the first few months to see if further capital investment is warranted.
So what's the most cost effective superconductor, that can be LN2 cooled?
None at this time. 77K superconductivity at reasonable Jc (current density) is not possible in strong magnetic fields. High fields require lower temperatures. For superconductivity electrons have to travel in pairs. Magnetic fields split the pairs. I think the Zeeman effect also describes this in a different domain (photon production from level "jumping").

What about DI-BSCCO wire? check out these articles:
http://www.highbeam.com/doc/1G1-80206544.html
http://www.sei.co.jp/news_e/press/04/04_06.html
http://www.greencarcongress.com/2008/06 ... lectr.html

MSimon · Post by **MSimon** » Fri Jan 30, 2009 7:05 pm

imaginatium wrote:
MSimon wrote:
imaginatium wrote: So what's the most cost effective superconductor, that can be LN2 cooled?
None at this time. 77K superconductivity at reasonable Jc (current density) is not possible in strong magnetic fields. High fields require lower temperatures. For superconductivity electrons have to travel in pairs. Magnetic fields split the pairs. I think the Zeeman effect also describes this in a different domain (photon production from level "jumping").
What about DI-BSCCO wire? check out these articles:
http://www.highbeam.com/doc/1G1-80206544.html
http://www.sei.co.jp/news_e/press/04/04_06.html
http://www.greencarcongress.com/2008/06 ... lectr.html

The question is: how well do the materials in those SCs tolerate a neutron flux?

imaginatium · Post by **imaginatium** » Fri Jan 30, 2009 7:37 pm

MSimon wrote: The question is: how well do the materials in those SCs tolerate a neutron flux?

Neutron flux? Aren't we talking about pB11?

MSimon · Post by **MSimon** » Fri Jan 30, 2009 9:31 pm

imaginatium wrote:
MSimon wrote: The question is: how well do the materials in those SCs tolerate a neutron flux?
Neutron flux? Aren't we talking about pB11?

pBj still has a neutron flux. About 1E6/cm sq S at the vessel walls IIRC. Side reactions.

imaginatium · Post by **imaginatium** » Fri Jan 30, 2009 10:19 pm

MSimon wrote:
imaginatium wrote:
MSimon wrote: The question is: how well do the materials in those SCs tolerate a neutron flux?
Neutron flux? Aren't we talking about pB11?
pBj still has a neutron flux. About 1E6/cm sq S at the vessel walls IIRC. Side reactions.

And that exceeds the tolerance of DI-BSCCO?

MSimon · Post by **MSimon** » Fri Jan 30, 2009 11:00 pm

imaginatium wrote:
MSimon wrote:
imaginatium wrote: Neutron flux? Aren't we talking about pB11?
pBj still has a neutron flux. About 1E6/cm sq S at the vessel walls IIRC. Side reactions.
And that exceeds the tolerance of DI-BSCCO?

Can't say for sure - my recollection is that MgB is equal or better (I think it is better by an order of magnitude). One thing MgB has going for it is ductility. Very important when winding coils.