Re: Metal Selection for gap.

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: Jim Lux <jimlux-at-earthlink-dot-net> 

At 07:44 AM 3/8/2004 -0700, you wrote:
>Original poster: Kurt Schraner <k.schraner-at-datacomm.ch>
>Luke,
>
>specific heat is not the only physical property, determining the 
>temperature of the electrodes. For the STATIONARY condition it's even not 
>relevant, but HEAT CONDUCTIVITY of the material is. Of course, stationary 
>heat transfer, is not exactly, what we have in spark gaps, and so you are 
>right to consider SPECIFIC HEAT as well. And DENSITY would needed to be 
>taken into account further, because
>
>   density * electrode volume * specific heat[J/kg]
>   --- electrode mass [kg]---
>
>
>              Density     specific heat  thermal cond. Tmelt
>              kg/liter       J/kg K        W/m K         C
>Copper         8.9            390          393        1083
>Tungsten      19.3            142          197        3380
>Brass MS72     8.56           390           92         920
>SS V2A         7.88           500           21        1400
>Zinc           7.14           376          109         419

there is an excellent discussion of this sort of thing in Strong's 1938 book
"Procedures in Experimental Physics" (available from Lindsay Publications 
http://www.lindsaybks-dot-com/  for $24.95)   An exceedingly useful book overall..
http://www.lindsaybks-dot-com/bks/expphy/index.html