QuenchFast / medium-speed oil (e.g. Parks 50 / AAA)
Temper2× 2 h · cool to room temp between cycles
Reliable hardness56–64 HRC
Simple eutectoid carbon steel — very forgiving, no soak fuss. Quench in fast oil within ~1s of the furnace.
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
60 HRC
500°F
260°C
58 HRC
Composition (typical, wt%)
Element
%
C
0.84%
Mn
0.75%
AISI 1084 typical (C 0.80–0.93, Mn 0.60–0.90)
HeatTreatBench — the recipes in your shop, offline
Get the full 1084 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.