Nickel-bearing — the bright layer in damascus with 1084/1080. Tough and shallow-hardening.
Temper → hardness chart
Approximate HRC after a double-temper at each temperature (from the sources below). Set your target and pick the matching temper.
Temper °F
Temper °C
Hardness
300°F
149°C
64 HRC
350°F
177°C
62 HRC
400°F
204°C
60 HRC
450°F
232°C
58 HRC
Composition (typical, wt%)
Element
%
C
0.75%
Ni
2%
Mn
0.4%
Si
0.3%
Uddeholmstrip 15N20 / NJSB mill certs
HeatTreatBench — the recipes in your shop, offline
Get the full 15N20 recipe plus 25 more steels offline — set your target HRC and the app gives you the exact temper, with a forge timer and a per-blade log. Works in the shop with no signal.