[time-nuts] OCXO housings - Why copper and not iron/steel?

[Andy Talbot]

Actually, diamond has five times better thermal conductivity than silver,
so is the most conductive element, although graphene is suspected to be
better still.


Andy
www.g4jnt.com



<http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
Virus-free.
www.avg.com
<http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

On Fri, 30 Oct 2020 at 22:17, Luiz Alberto Saba <las at intercat.com.br> wrote:

> My bad... copper is the second, losing only to silver, as a thermal
> conductor.
>
> Enviado do meu iPhone
>
> > Em 30 de out. de 2020, à(s) 19:06, Luiz Alberto Saba <
> las at intercat.com.br> escreveu:
> >
> > If my memory serves me, copper has the better conductivity of all the
> periodic table...
> >
> > Enviado do meu iPhone
> >
> >> Em 30 de out. de 2020, à(s) 18:56, Attila Kinali <attila at kinali.ch>
> escreveu:
> >>
> >> Moin,
> >>
> >> I have been looking at heat capacities of different materials
> >> lately. One thing that struk me odd is, that the volumetric
> >> heat capacity of copper, which is the thing that most people
> >> use when building something that needs to have high heat capacity
> >> to get stable temperature, has only a volumetric heat capacity
> >> of 3.45 J/(cm^3·K). Meanwhile, the much cheaper iron has
> >> a volumetric heat capacity of 3.53 J/(cm^3·K) and steel
> >> even 3.75 J/(cm^3·K).
> >>
> >> In an OCXO, which is generally size limited, getting the most
> >> heat capacity in the limited volume would be the main goal,
> >> wouldn't it? Also optimizing for price would be a major thing.
> >> I can understand that iron is probably not the right choice
> >> due to its tendency to oxidize. But using a soft (annealed) steel
> >> would be easy to machine, cheaper per piece and give almost 10%
> >> higher heat capacity in the same volume.
> >>
> >> So why do people choose copper instead of steel?
> >>
> >>
> >>           Attila Kinali
> >>
> >> PS: Fun fact: Water has a volumetric heat capacity of 4.18 J/(cm^3·K)
> >> at 25°C. We should fill OCXOs with water! :-D
> >>
> >> --
> >> <JaberWorky>    The bad part of Zurich is where the degenerates
> >>               throw DARK chocolate at you.
> >>
> >> _______________________________________________
> >> time-nuts mailing list -- time-nuts at lists.febo.com
> >> To unsubscribe, go to
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> >> and follow the instructions there.
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts at lists.febo.com
> To unsubscribe, go to
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.
>