12 years ago
chunk of steel in my ash bucket. Last week I ran a very similar test
using vermiculite instead of the ashes from my coal forge. I was
shocked to see that the part cooled much faster in the vermiculite
(about 600°F in the first hour)than it had in the ashes (about 300°F in
the first hour).
Does anybody here have data that would support or refute this finding?
I did find one blacksmith related site where the guy said about the same
thing, but his experience was apparently anecdotal.
For what it's worth, either annealing medium will work pretty well for
plain carbon steels, and maybe for 4140. But it won't do much for even
01 let alone S7 or other air hardening steels.
I already have the "ashes" test data and graph on blacksmith portion of
my website and I will make a page for the vermiculite results if some of
you are interested.