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
62 HRC
350°F
177°C
61 HRC
400°F
204°C
60.5 HRC
450°F
232°C
60 HRC
Composition (typical, wt%)
Element
%
C
1.05%
Cr
14%
Mo
4%
Niagara / Crucible CPM 154 datasheet
HeatTreatBench — the recipes in your shop, offline
Get the full CPM-154 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.