sal wrote:Title says it. What are your thoughts?
Don't use hardness as a means to judge how to harden steel.
There are a few general ways to approach it based on what you are trying to achieve :
-If you want a balance of strength/toughness/wear resistance then soak just enough to put ~0.6% carbon in solution, leave most of the chromium undissolved, use an agitated oil quench to ensure minimal diffusion, cryogenics (if possible), to reduce retained austenite, and then temper ~350 F to 400F to get the plastic zone you want. Joe Calton has a video recently where he shows a very simple check you can do to estimate the start and extent of the plastic zone with very basic materials.
-If you want a very high toughness/durability then reduce the soak time a little, don't use cryogenics, and temper just in front of the 500F embrittlement zone. This will give a blade with a much wider plastic zone but a reduced strength and wear resistance.
-If you don't care much about toughness then soak a little hotter/longer, it is critical to use cryogenics as the retained austenite will be very high, and temper low, 325-350F. This gives the highest strength and wear resistance but you won't have much plastic deformation at all.
There are guys on HypeFree who have the exact cycles on each one of these and have described how they behave in terms of rope cut and flex and impact tests. Most people tend to do the first one because it tends to have decent performance over a broad range of tasks and users.