"JRJohnson" wrote in message
...
SNIP
| Do fuel rods have an outer sheath of mild steel? Don't think so, but this
| was obviously constructed to hold the 'swarf' (for lack of a better term)
in
| the center hole. Still beats the hell out of me.
|
| Research into zirconium was productive only in that I learned that the
| melting temp was around 3350 degrees F.
|
| Still wondering, JRJ

Something just came to me. What's the possibility this is a valve stem
from a large industrial engine? Seems to make sense, but I don't know big
engines. You talked about the heating problem, where the thermal
conductivity of the part was really high, you had a hard steel outside, and
the copper ensured that the center, which served as the heat conductor, was
able to transfer the heat nicely. Does this make sense?