View Full Version : Question On HT Of 154CM


CDS
03-21-2004, 11:41 AM
Hello Everyone,
I have done some searching on this, but have not come up with much. I am following the direction on HT for 154CM from Crucible's web site. Although I do not have the means of performing a cryo treatment, I was wondering if a second tempering would be needed? I see this mentioned alot about 2 & 3 tempering's but there is no instruction about a second tempering on the Crucible directions, unless you are doing a cryo. Any experience is greatly appreciated!
Chris S.

Jerry Hossom
03-21-2004, 01:30 PM
The short answer is "yes" and that's generally true of most all steels.

rlinger
03-21-2004, 03:48 PM
As Jerry says. Temper your stainless steels twice for a minimum of 2 hours per. I like dropping my second temper temperature about 20 to 25 degrees F less than the first temper. This helps preserve the hardness achieved by the primary temper yet provides a proper finishing temper.

Roger (RL)

CDS
03-22-2004, 04:11 PM
Hello Everyone,
I just wanted you to know that my first HT seemed to be a success! I followed the Crucible directions and yours about a second temper exactly.
154CM Blade inserted cold:
Ramp To: 1250 Equalize
Ramp To: 1450 Equalize
Soak: 1950/1Hour
Rapid Quench: (see below)
Immediate Temper: 400/2Hours
2nd Temper: 375/2Hours
I obtained a "Dead-On" 59RC(Benchtop Tested) on both blades. Is this too much/high?? I think Crucible's information said I should obtain a 56RC rating with this recipe.
Quenching was performed with 1" thick aluminum plates. Temperature was reduced from 1950 to below 125 in about 20 seconds! I could not believe it! No warping on the blades either.
Thanks for the comments.

rlinger
03-22-2004, 04:37 PM
59 HRc is dead on for what you did without a deep freeze. It is the target hardness you should expect. You should not have to soak so long in the future for your knife blades. I usually soak ATS-34 and 154CM for about 27 minutes.

RL

Jerry Hossom
03-22-2004, 07:37 PM
Yeah, your soak time is quite a bit longer than needed. Most specs in the Crucible tables are for much thicker sections than knives. 15-20 minutes is sufficient. Paul Bos tempers 154CM/ATS-34 at 950F to get to Rc61 with cryo.

rlinger
03-24-2004, 11:09 PM
It is suggested that an under soak of stainless is worse than soaking a little too long. We need to get the complex alloy soaked thoroughly. In testings I have found about 27 minutes is better than less than that for good grain structure. Steels of high vanadium content may well be better soaked a bit longer, but I have not tryed soaking S30V longer than about 27 minutes yet.

RL