S35VN heat treat. Suggestions? First try not so good.

[godogs57]

Bought a stick from Pop’s in addition to my usual CPM154. Was told by a few folks they just “throw it in” with CPM154 and it’ll come out just fine. Mine didn’t. I researched Crucible’s data sheet and their recommendation was 1950 @ 15-30 minutes with a double temper @ 600. I ht my CPM154 @1950/30 minutes, triple temper @ 400 and get 60.5-61.0 every time. (aluminum plate quench out of the oven)

My last batch of CPM154 included a blade of S35VN. After temper, I got the usual 60.5 on the CPM154, but was not happy to see I only got a 58 with the S35.

I noticed I can take the S35VN up to 2000 degrees....perhaps I need to bump it up a bit?

 

[Larrin]

My heat treatment recommendations for S35VN are for cryo: https://knifesteelnerds.com/2020/01/13/s35vn-steel-properties-and-how-to-heat-treat/

But the datasheet shows 57.5 Rc for 1950-400 without cryo so if anything your 58.5 was high.

 

[godogs57]

Thank you. Agreed with your conclusion: 2025@15min, etc, etc....
I need to find a way to cryo my blades I suppose

 

[Willie71]

Thank you. Agreed with your conclusion: 2025@15min, etc, etc....
I need to find a way to cryo my blades I suppose

Sub zero will work just fine with s35vn. You can get an extra Rc point with LN over sub zero with higher aust temps, as there is more retained austenite to convert as aust temp goes up. If you are aiming for Rc60/61, sub zero is perfectly adequate.

 

[Ken H>]

Willie: When you say "sub zero", do you mean -5°F or dry ice temps of -95°?

 

[Willie71]

Willie: When you say "sub zero", do you mean -5°F or dry ice temps of -95°?

I use the terms sub zero for dry ice/acetone, and cryo for LN.