Cpm 154 Ht?

Michael J. Spangler

Michael J. Spangler

Joined
Oct 8, 2003
Messages
2,181
alright guys i kow its been posted but i always have too much trouble with the search function. any other links on stainless HT info would be awesome too. i need to get a dewar next. is there any container i can put LN just for one time use/transport? i can't go and get a dewar right now, but if there's another options i'd like to just buy some do a batch of steel and i'll be set for a while. thanks in advance
 
Per Peters' Heat Treat in PA...

Our standard cycle is as follows: harden @ 1950F , soak at temp. for 30 minutes, quench w/ N2 down to room temp. We then go straight to the cryo w/ most
orders( very delicate jobs may get a 300F temper prior to cryo), -300F/ 4hrs. The parts are allowed to return naturally to room temp., then we begin the tempering
process. For ATS/154 this is 980-1020F for 2hrs. @ temp. X2 or maybe X3.

Instead of LN you can also use dry ice / alcohol bath which gives you a -100 degree bath. Not optimum but sufficient from what I've heard for near cryo treat. I'm sure one of the meta's will jump all over me for saying that...just passing on what I've read. Good luck!
 
i run it a little hotter soak a bit shorter and temper it cooler 2000f soak 20 min plate quench -Ln over night then temper 400 2x2hours
this is the kitchen knife work i do and they like it hard and sharp Rc62. i run aust temp 1975 20 min all the rest the same for hunters (Rc60-61)

remember all kilns will read different so my 2000-2015 might be there 1950 going to ahv eot have at least a test blank or 2 to get in "your" zone
 
I agree with the 1950 temp and I use 30 - 45 min depending on thickness. Longer soaks = better uniformity as long as O2 is excluded (within reason). From room temperature (plate quench), I go straight to Liquid Nitrogen - overnight. Next morning back to room temp and double temper - never in the high range for these steels - 450 for hard as stink - 500 for a little easier to sharpen.

IMHO, dry ice / acteone is just as effective but harder to keep for any time.

I might consider a flash temper if I had a Gil Hibben fantasy knife - or a deep guthook or something - but I haven't seen the need yet. Maximumum benefit is to cryo as a continuation of the quench. I just took it from 1950 to room temp in about 90 seconds. What's another 300?

Once you've cryo'ed CPM 154, it's really hard to screw it up. Sweet stuff!

Rob!
 
Rob et all, I have had good results with a preheat at 1500, ramp to 1940 to 1960 hold 40 min. cool in front of a fan and into LN2 as soon as it comes to RT. LN2 for at least 2 hours, Temper at 400 3 times for 1 hour each for a finished hardness of 62. I use Turco for decarb protection. This is what I am using for Clients knives, for a couple of my own I have used 950 temper and so far cannot see any negative results. My thinking is that the better structure due to the CPM make up allows for a suffiecient toughness even with a thin ground blade(0.10 behind the edge bevel). The result of the higher temper is a finished hardness of 63. I was able to shave a brass rod with this HT without any major chipping. Corrosion resistance and impact toughness I know will be a tad lower and need some field work to check that out better. I am not reccommending this just some more info for those who like experiment around a little. The next batch of heat treat I'm going to try oil quench. If anyone gets some time to try this I would appreciate hearing what they think.
 
Michael, you can email me if you like. I have done quite a bit of ATS-34 and CPM S30V with and without cryogenic as part of the HT. Soaking too long will not be good and tempering as high as some data sheet specs call can compromise corrosive resistance. I can share my notes with you if you like. I think you used to do thicker blades than I but its all relative. As for the LN: I wouldn't trust it for long enough, or for safety sake, in any other container than a dewar. Dry ice should help transform some retained austenite but not to the extent of a deep cryo, such as liquid nitrogen will perform.

rlinger
------
 
Oops, amendment to mine...not alcohol, acetone. Duh. Sorry 'bout that....
 
hmmm. all good info. now are there any steels where the acetone and dry ice can fully do the job? i know some steels need the LN but are there any where maretnsite finishes forming at a temp that can be reaches by the dry ice method? thanks a lot guys.

i have some 154CM some Ats34 and then the CPm154 to work with right now. just wanna use whatever i can give a full good HTing to.
 
For the simple size and shape of a blade the preheat is not necessary. ...You will never transform all the retained austenite in an alloy like that and a little bit won't hurt. Without cryo will work as Roger says, CO2 will remove more , and LN will remove even more !!
 
Michael,
This is one of those places were semantics really matters.
When you say FULLY and ANY STEELS, you have opened many doors. Many simpler carbon steels and low alloy steels would do fine in -100F dry ice/ acetone (many won't benefit at all ). When you move to high alloy stainless steels, you enter a different door. That's where the word fully comes in. If you mean 100% of possible, then, NO most will be better off with -200 than -100. However, most basic stainless steel will do fine in dry ice/acetone. There may be a small percentage of unconverted austenite, but it will not greatly affect the blade, and the blade will have benefited from the cryo treatment. That said, LN is usually easier to do, store, handle, etc - and does all that cryo can do.
Stacy
 
yeah i was just wondering if there were any stainless steels that only need to go to
-100 or if they all need the cryo. kind of tough to find some info on it.

thanks for the info.
 
Michael, I would not spend a bunch of time or money fooling around with CO2. If you had the time and ability to keep the CO2 refreshed for the blade to age long enough at ~ -100F it would work. Lower temperatures decrease aging time. I am sure you already know the only, but very substantial, benefit you will realize is retained austenite transforming to UNTEMPERED martensite. If you really want to cryo on a regular basis go with LN. The ice won't hurt a bit though, especially for just a blade here and there.

rlinger
------
 
I put blade in the oven at 1000 F and ramp up to 1400 F for 15min. Then ramp up to 1950 for 35 to 45 min depending on thickness. Plate quench. Then Cryo in LN overnight. Temper twice at 500 F for 2 hours each time.
-John
 
alright i'm going to go for it... gonna ht some steel today... the beast is working and quite well might i add.... well as far as i've seen

so i'm going to go with the CPM 154

becasue i happen to have a few blades sitting around. too anxious to go grind some ats or something. can't wait been waiting too long.

okso i'm going to go with 1450 for 10 minutes, then 1950 for 45 minutes. then plate quench. then i'm going to go with 475 temper for 2 hours.... now the question is

can i temper, then get dry ice monday and treat it with that then temper again? will that work? i don't know too much but i figure there won't be any any kind of crazy stress because its all austenite and not untempered martensite right?

the local dry ice supplier is bone dry,and so is their supplier so there won't be any in the area untill monday. thanks in advance guys

p.s. what is the percent of retained austenite in this steel if not cryoed?
 
I think it's best to cryo or dry ice bath right after heat treat. I have heard of people cryo or dry ice bath in between the two tempers.
 
You could 'snap temper ' at 300 F before cryo.Retained austenite percentage - you would have to ask Crucible. You will never remove all of it but if you HT properly it won't be a problem.
 
TekSec said:
Per Peters' Heat Treat in PA...

Our standard cycle is as follows: harden @ 1950F , soak at temp. for 30 minutes, quench w/ N2 down to room temp. We then go straight to the cryo w/ most
orders( very delicate jobs may get a 300F temper prior to cryo), -300F/ 4hrs. The parts are allowed to return naturally to room temp., then we begin the tempering
process. For ATS/154 this is 980-1020F for 2hrs. @ temp. X2 or maybe X3.

Instead of LN you can also use dry ice / alcohol bath which gives you a -100 degree bath. Not optimum but sufficient from what I've heard for near cryo treat. I'm sure one of the meta's will jump all over me for saying that...just passing on what I've read. Good luck!
Click to expand...

Erik,
The lowest you can get with dry ice/ alcohol is about -55 degrees F. I use it all the time to freeze bearings for installation, and this is the industry standard information in our maintenance seminars.

Ickie
 
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