J. Doyle
Dealer - Purveyor
from Alpha knife supply:
15n20 Heat Treating Information:
Austenitize: Heat to 1480°. Quench in oil.
Temper: Temper at least once for 30 minutes. Tempering twice for two hours each time is preferred. Use the table below to achieve desired hardness.
1080 Heat Treating Information:
Austenitize: Heat to 1545°-1615° and hold for 5 minutes. Quench in oil.
Temper: Temper twice for two hours each time. Use the table below to achieve desired hardness.
Insofar as a neophyte like me can determine, the two different steels above call for different heat treat formulas.
Note: I don't think Alpha, despite its name, is part of the knifemaking aristocracy.
I wanted to point out something in this post..........the first example shows heat treating data for 15n20.
The second example says it's heat treating data for 1080 but it really is data for "1080+ (plus)" which really is not like standard 1080 at all but more like 5160 with a lot more carbon.
I've used quite a bit of this 1080+ from Alpha and it really shouldn't be treated the same as 1080 at all.
Just wanted to clear up that it's not standard 1080.
I think the data for standard 1080 would read very similar to the data and chart in the first example for 15n20.