QuenchPlate quench (aluminum plates); datasheet: air or 2-bar gas to below 125°F
Cryo / sub-zeroOptional — dry ice / LN2 — datasheet allows a freeze between tempers; maker practice is right after quench. Datasheet hardness column assumes -112°F freeze
Temper2× 2 h · cool to room temp between cycles
Reliable hardness58–61 HRC
The benchmark PM stainless (2001). Crucible recommended HT: 1950°F, quench, double temper 600°F → aim 58–61. Datasheet @1950°F + freeze: 400°F→60.5, 600°F→58.5. Larrin suggests 2025–2050°F + 400°F for a better toughness balance at ~61. Temper window 400–750°F; vacuum/atmosphere quench can run 1–2 HRC lower.
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
400°F
204°C
60.5 HRC
600°F
316°C
58.5 HRC
Composition (typical, wt%)
Element
%
C
1.45%
Cr
14%
V
4%
Mo
2%
Niagara / Crucible CPM S30V datasheet
HeatTreatBench — the recipes in your shop, offline
Get the full CPM-S30V 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.