View Full Version : Heat treating 154 CM


Tbonz
09-30-2004, 10:22 PM
I will be doing my own heat treating in the future and I would like to start with 154 CM. I checked a few sites but I have not located a formula for heat treating 154 CM yet. Is there a site or book available that describes the process for heat treating 154 CM and other steels used by knife makers?

Thanks
Tim

Jamey Saunders
09-30-2004, 10:43 PM
I believe that you can use the recipe for ATS-34, as it is basically the same steel as 154 CM. Somebody else correct me if I'm wrong...

mete
10-01-2004, 05:12 AM
ATS-34 is made by Hitachi and they list two heat treat procedures. 154-CM is essentially the same steel and you can find heat treat info on www.crucibleservice.com .You want to start heat treating with 154-CM ? These steels are complex steels and require very precise times and temperatures and are not for beginners. Far easier to use would be something like 5160 or 1080. If you want to make a stainless steel knife I suggest you send it out for heat treating.

Tbonz
10-01-2004, 08:41 AM
I did not realize that heat treating 154 CM or other stainless steels would beyond home heat treating. I was hoping that I could use the Evenheat oven I purchased to do this type of Heat treating.
What are some steels other than 1080 and 5160 that can be heat treated in an evenheat oven by a beginner.
How about 1095 or 01 tool steel?

Jamey Saunders
10-01-2004, 08:59 AM
I think what Mete was saying was not that it can't be done, just that the recipe is more difficult to follow. It's certainly possible, as many, many makers are heat treating these steels in their shop. Unless you're very careful in every step of your process, you won't get the optimal HT. Something simpler and a little more forgiving may be in order until you get the hang of the process. 440C comes to mind as a very good knife steel (just not as glamourous) with a fairly forgiving HT formula for a stainless.

However, if you wish to use 154CM, go ahead and experiment. Just follow the recipe very closely, and don't be afraid to toss a blade if you think you may have monked up the HT.

Don Robinson
10-01-2004, 11:27 AM
The recipe is the same for ATS34 and 154CM. Both have a secondary hardening curve, which means you can use the lower heat cycle (I recommend this one), or go to the secondary cycle and temper at a much higher temperature.

The lower temp. cycle gives the steel more toughness, but working hardness and edge holding remain the same, depending on the tempering temperature.

Using the lower cycle is commonly referred to by heat treaters as "underhardening", but this is misleading. The steel is still brought past the desired hardness, then drawn back to final working hardness.

With your Evenheat furnace and a digital controller, there is no reason not to do it yourself, but as others have warned, be very careful to follow the recipe.

Since I assume you don't have controlled atmosphere, you need to use stainless steel foil wrap to prevent scale and decarburization during the hardening cycle. this isn't necessary during tempering.

After many years of heat treating ATS34 and 154CM, here is my recipe for a knife blade under 1/4" thick.

1. Preheat the furnace (it's a furnace, not an oven) to 1200 degrees and hold for 30 minutes or so to remove any moisture from the lining.
2. Preheat the furnace to 1920 degrees F.
3. Wrap the blade in the foil and double wrap and crease the edge and both ends of the package. Add a small piece of paper towel or cotton before sealing the last end. The organic material will attract the oxygen left in the pkg. Bend the end of the wrapper at the tang end of the blade, so you will recognize the tang end when you remove the wrapper.
4. Place the blade pkg. into the furnace, wait for the controller to bring the temp back up to 1920, and soak for 16-20 minutes. Any more time is unnecessary, and will damage the steel.
5. Now have all your ducks lined up in a row. Remove the pkg. and immediately cut the pkg. off the blade with scissors. Be sure to cut the bent end of the package. where the blade tang is. If you cut the point end, you will damage or cut off the point. Seconds count here.
6.Place the blade onto a flat heavy piece of steel, then place another heavy flat piece of steel on top of the blade. The steel acts as a heat sink, giving a more rapid cooling than an air quench, which is a good thing.
7.After you can touch the blade with your hands without burning, you must immediately flash temper the blade to prevent stress cracks. Place the blade into your kitchen oven set at 325 degrees F. Leave it in at least an hour. Two hrs. is good.
8. When your heat treat furnace cools down, set the controller at 390-400 degrees for 2 hrs. Place the blade into the furnace, let it come back to the set temp., and temper it for 2 hours.
9.Remove and let the blade come down to room temp.
10. Repeat the temper at the same setting for 2 more hrs.
10. You're done. Simple, huh?

Email me from my web site and I'll send you the Hitachi TTT chart by email.

You're welcome.

mete
10-01-2004, 04:42 PM
Don, please comment on whether you have used aluminum quench plates and cryo .

Tbonz
10-01-2004, 05:38 PM
Thanks to Jamey and Don for their input.

Jamey thanks for the suggestion of trying my hand at 440C stainless before taking on a steel that will require a more exacting process. I'll purchase some 440C and get some practice before moving on to 154CM or ATS34.

I have some blades made of 01 Tool steel that I have waiting to be Heat Treated, these will be the first blades that I Heat Treat. Hopefully I can find some info on heat treating 01 in the forums posts.

Don,
Thanks for the clear and concise information on how you HT 154CM / ATS34.

tmickley
10-01-2004, 06:01 PM
Don is the machinist here and knows more than me on just about everything metal.

I double wrap the blade with a little piece of paper.
Chunk it in the cold furnace
Ramp up to 1400 as fast possible, soak for 5 minutes (these are .1 thin folder blades)
ramp up again to 1950, soak for 30 minutes
grab it, foil and all, hold it verticle above a fan funneled into a tube
in the mean time I have a little toaster oven holding at 300
when the blade is cool enough to barely hold (hot tater!)
hold it in the toaster oven until the furnace cools to 450
soak at 450 1 hour, cool to room temp, soak again
done, RC 59

If you are doing a cryo, after the initial 'quench', cool to room temp, cryo for 8 hours in liquid N or dry ice w/#1 Kerosine.
This gets it to 61 RC
then do the double temper at 450

this is basically from the crucible heat data and the RC's come out dead on.

Don Robinson
10-01-2004, 06:17 PM
Don, please comment on whether you have used aluminum quench plates and cryo .

:) Sure will, Mete.

Aluminum works fine, but it's expensive. I use scrap steel from a punch press die.

I've used both liquid nitrogen,and dry ice/acetone for a cryo quench, and it does usually raise the final hardness one or two points. The problem is that you can't predict the final hardness with cryo. I adjust the hardness of every blade during the final tempering cycle to suit the purpose/untended usage of the blade. For rough use, I want 58Rc. For everyday usage in a small knife, I like 60Rc. I don't like to use a working hardness above 60Rc because I'm afraid the edge might chip. With cryo, it may raise the hardness 1 or 2 points, but you can't predict the results. I'm not satisfied with that, so I don't cryo any more.

ATS 34 or 154 CM makes such a good blade without cryo that I'm pleased with it as is.

It might help to know that I have a Rockwell hardness tester, so I know the exact results after quench and between tempering cycles.

As you know, each batch of steel from the mill will vary a little in chemical content, and the steel makers have a tolerance range. That means you can't predict closer than 3 hardness points the after-quench hardness. I keep a written record of each blade, so I can predict the results of succeeding blades from the same bar. The next bar may come from a different batch, though, so you have to start over.

Most commercial heat treaters will only work within a 3 pt. range for the above reason. They can't afford to test every blade after quench and between tempers like I do.
;)

rlinger
10-02-2004, 12:35 AM
Here you go: foil wrap the blade. Do not double wrap unless you can remove the blade quick enough for quenching. Double wraping is absolutely unnecessary when a single is properly wraped and temperature specifications are not exceeded. I single wrap and rapid air quench while in the foil packet. If you can quickly remove the blade without distorting it very good for you and by all means do so.

Place the foil wraped blade in cool oven.

Ramp moderately to preheat: Preheat @ 1400 - 1410 / 7 minutes

Ramp as quickly as possible to austenitizing: Austenitize @ 1950 / 25 minutes

Rapid air quench (if you can remove from packet quickly you may warm oil quench)

Snap temper @ about 325 F / 1 hour

Place in deep cryo (10 - 12 hours) IMMEDIATELY upon assuming room temperature

Upon warming to room temperature temper @ about 525 F / 2 hours

Allow to cool to hand warm

Temper @ 500 F / 2 hours
--------------------------------
Expect approx. 59.5 HRc if rapid air quenched

RL

Tbonz
10-04-2004, 08:26 AM
1. When removing the foil wrapped blade from furnance what kind of tool is used?
2. If you put a piece of paper in the foil wrap should it be touching the blade or wrapped so its not touching blade.
3. How big a pice of paper?
4. What thickness should quench plates be? When the blade is put between the quench plates is it still in the foil wrapper or is the wrapper removed and discarded after the first step in HT?
5. Should the blade be tempered as soon as possible after the first step is completed?
Thanks

Don Robinson
10-04-2004, 09:42 AM
1. When removing the foil wrapped blade from furnance what kind of tool is used?
2. If you put a piece of paper in the foil wrap should it be touching the blade or wrapped so its not touching blade.
3. How big a pice of paper?
4. What thickness should quench plates be? When the blade is put between the quench plates is it still in the foil wrapper or is the wrapper removed and discarded after the first step in HT?
5. Should the blade be tempered as soon as possible after the first step is completed?
Thanks

1. Tongs. If you don't have blacksmith tongs, then do what I did. Buy an automotive brake spring removal plier, heat the ends of the jaws, bend the jaws toward each other to act as tongs. I welded a longer rod on the handles to extend the reach. Always wear a pair of heavy leather gloves with long cuffs that reach way up on your arms.
Welder's gloves.

2. Doesn't matter. It turns into ash.

3. I just pull approximately a 2" square off the corner of a paper towel.

Several pounds. This will keep the blade from warping and speed the quench.
See step 5. Always remove the wrapper first. Cut the end off and shake the blade out gently or pull it out with pliers from the tang end. IMPORTANT! At this point the blade is plastic, and will bend extremely easily. If the point touches anything, it will bend over. ALWAYS handle carefully from the tang end, using pliers if necessary.

5. See step 7 above. You must flash temper as soon as the steel reaches room temp.to prevent stress cracks.

cramnhoj
10-29-2004, 02:26 AM
I've got a question, in the Bob Terzoula knifemaking book, he says he tempers ATS-34 at the higher temps (around 900-1000 degrees F) because he says based on his experience, doing it at around 400 degrees F results in a brittle blade. However in the Crucible data sheet for 154CM it says martensitic steels result in brittleness when tempered in the 800-1100 degrees F and the 400 degrees F was recommended.

So which one should I listen to? I'm looking into working on 154CM, and since people say it's basically the same as ATS-34 I thought Terzoula's advise on ATS-34 would also apply on the 154CM.

Don Robinson
10-29-2004, 10:08 AM
Tempering 154CM or ATS34 in the lower range results in a tougher, less brittle blade.

Hitachi is correct.

RJ Martin
10-29-2004, 10:43 AM
I have to disagree with a few things that have been said here. I do not see any advantage to removing the blades from the foil package prior to press quenching. Leaving the blades in the packets prevents any oxidation, helps you get the blades into the plates at least 10-15 seconds faster, and eliminates bending the red-hot blades when they are removed from the packets. The heat transfer from the blades to the plates is not impeded by the foil. Plus, using this method, you can make a big pack, containing several blades of the same thickness, lying horizontally and get them from the furnace to the quench plates all at the same time. No more opening and closing the furnace door with blades inside waiting to be quenched.
After heat treating several thousand blades, I am sold on this method. Once the blades have cooled below 900F, I open the foil, remove the blades and put them back between the plates until they are just cool enough to touch. Then, I snap temper. and cryo.

I am checking with Crucible about the low temperature temnpering of 154CM. My understanding is that more consistent results are obtained with the higher temp tempering, performed at least twice, but, I will report back after I speak with them.

rlinger
10-29-2004, 10:51 AM
In general, tempering stainless steels at the high end results in loss of corrosion resistance. I temper ATS-34 and its cousins, such as 154CM, at about 400 F.

RL

SteveS
10-29-2004, 12:11 PM
After heat treating several thousand blades, I am sold on this method.

Gee I came to that conclusion after 4 blades. ;) ;)

Really tho, it's nice to know there's a pro out there quenching with plates in the packets. Makes me feel better about it. I certainly do like the ease and no muss & fuss with this approach.

Steve

R. D. Finch
10-29-2004, 10:53 PM
Tbonz

I started doing my own heat treating this year using the Evenheat Furnace, I'm still experimenting, but I use Don Robinson method. He is very helpful and will answer email.
I use 1/2" aluminum plates.

Don Robinson
10-30-2004, 01:31 PM
There is nothing wrong with quenching the package before removing the foil. I remove the foil before quenching because I use the plates to hold the blade flat.

If you don't remove the foil, something, maybe a crease or the folded edge of the pkg. may keep the plates from contacting the parallell surfaces of the blade.

:( Murphy's law always applies.

I simply prefer not to take any chances. I sometimes wrap two similar blades together, But I remove the foil and lay them out flat before stacking the second quench plate on.

By the way, one of my statements may have been mis-interpreted. I didn't mean to double wrap the blade. What I meant was to double wrap the edge folds. A single fold isn't enough to seal the package.

Best wishes to all.

Tbonz
11-18-2004, 08:08 AM
I finally got my Heat Treat station up and running last weekend and did some Heat Treating. My second Heat Treat project was with 154 CM and it came out. I used the information that was provided in this thread and I could not be more pleased. I'm not sure what the RC hardness is because I do not have any testing equipment. But it is hard and if I did the tempering correctly I imagine it is in the 58 to 59 RC range.

If I want to heat treat 154 CM for use as a backspring and end up with a RC hardness of 43 to 45 how would I temper it?
I looked at some info and if I interperted it correctly I should temper at 1200 degrees for two hours, twice. Does that sound right?

rlinger
11-28-2004, 04:01 AM
I would guess so but would suggest soaking at the lower temperture of about 1900 F. I presume your air quench will be of rapid air flow. It is essential, regardless of type of quench, to always be as speedy as possible. You also know that corrosion resistance will be greatly comprimised at such high tempering temperatures. The reason I suggest the lower end of austenitization is because of possible grain growth. After all, in this case you are wanting a spring. You may want to first temper closer to 1100 F and test before going to 1200 F for your spring. I wonder about using such a stainless as a spring. My inexperienced guess is it is not a real good choice.

My mental block with using quench plates is blade geometry. If grinding bevels after heat treat my problem with it disappears. It is most important to quench the most essential buisiness part of the blade, the edge portion - which those plates do not contact during quench. People say "well those plates suck the heat so fast". Yes, but it all flows from the edge to a cooler spine and if the thicker spine is not cooler than the thin edge it will not sink the heat until it is cooler. So no matter how you cut it those portions not in contact with quenchant will always lag behind during those initial critical moments.

RL

RJ Martin
11-28-2004, 08:38 AM
RL: Despite what you think about quench plates, the fact of the matter is that they will quench a beveled blade to room temperature faster than any readily available method, except perhaps positive pressure Nitrogen gas, which is not available to most in-house heat treaters.

Yesterday I heat treated 10 S30V blades. .176 thick with deep hollow grinds done on a 10" wheel. The center of the edge was .088 from each plate. The blades were cooled to the point where I could comfortably hold them in my bare hand in under 60 seconds. Yes, he edges were a bit warmer than the spines, but
check your data. That rate far exceeds the required quench rate.
In addition, I had Crucible analyze my HT results-The photo micrographs were textbook, and, they ground specimens taken from the edge flat so that they could check the hardness. The hardness at the edge was the same as the hardness at the spine.

The whole in-house heat treatment issue has been bashed by some makers who use commercial heat treaters and have their own agendas, trying to claim that their knives are somehow better. This is simply not the case. In-house HT can yield great results.

Consider your quench options for an air hardened steel Austenitized in SS foil: Still air, fan forced air, compressed air, warm oil, quench plates. With these methods, you have the option to remove the blade prior to quench, or leave it in the foil. Even if you are lightening fast, the only option that rivals the cooling rate of quench plates is the warm oil quench, and, you have no protection from warping and scale. Compressed air is fast, but, not easy to apply uniformly to the entire blade. Quench plates allow you to quench in the foil, permitting the fastest time possible from furnace to quench. The rate of heat transfer into Aluminum is far greater than that of air.

Lastly, consider that you can cool most air hardening steels in still air and still have the blade harden. What does that tell you about the required quench rate?

Aluminum quench plates are about as good as it gets for rapid quenching for the in-house heat treater.

tmickley
11-28-2004, 08:50 AM
RJ, you've sold me. I have to try quench plates. What size do I need? (off to the junk yard...)

Don Robinson
11-28-2004, 09:21 AM
R.J., thanks for the re-inforcement about the quench plates.

I have a question for you, since you're familiar with S30V. I've just gotten my first order where the buyer insists on S30V.

I've seen discussions on the forums about troubles getting consistant results with powdered steels.

I ordered the Crucible TTT chart with the steel, and, of course, can come up with my own recipe. Do you use the Crucible TTT chart, and is it accurate and reliable, as I trust it will be?

Thanks.

RJ Martin
11-28-2004, 10:14 AM
Don: Actually, I have not received a TTT from Crucible for S30V. I asked for one a while ago, but it wasn't available then. Asking if you can trust Crucible's data is a little like asking if you can trust Alan Greenspan for financial advice. OF COURSE YOU CAN!!!!!!
I heat treat S30V as follows: Starting in a cold furnace, I ramp to 1600F in 35 minutes (yes, I have a fast furnace!) Using 1600F permits the blades to reach 1550-1600F due to a slight lag in temperature in the blades as they heat up. I soak 10 minutes, then ramp to 1960F in 20 min and soak for 20 minutes, 25 minutes for large blades. Then, I quench between the AL plates. After about 45-60 seconds of quench, I quickly remove the blades from the foil and place back between the plates for about 15-30 seconds, then temper 1 hour @550F, then freeze and re-temper 2X at temperatures between 500F and 600F, depending on the Rc hardness after freeze. You should be able to hit Rc59-60 easily this way.
BTW, my blades are horizontal in the package, and the package lays on a 3" high firebrick (low density) that runs down the center of the furnace.
I think the reason some makers have trouble with these steels is that their furnace and/or hardness tester aren't totally accurate (not calibrated). The more you heat treat this steel, the more experience you gain, and, that builds confidence. You have to have confidence to get the best results.....

Don Robinson
11-28-2004, 01:34 PM
Thanks, RJ.

I put the blade in its pkg. vertical with the edge up in my furnace. Supported between two small pieces of ceramic hearth plates. That puts the edge closest to the thermocouple.

If you want the TTT chart, I'll send it to you by email. Send me your address.

If everyone knew how to use a TTT chart, there wouldn't be so many problems for some.

I won't buy tool steel the first time without getting a chart. The response from some of the sales people is kind of pathetic: What's that? If you insist, they'll find it. :rolleyes:

I ordered my first CPM S30V recently from Koval, and the sales person had to look for the chart. At least, he knew what it was.

Maybe a good new topic and sticky for this forum would be a show and tell on how to get and read a TTT chart.

I use Hitachi's for ATS34, and it's right on the money, within 3 hardness points, and that depends on the chemistry of each batch. :)

RJ Martin
11-28-2004, 02:16 PM
Don: Edge up orientation is fine. Remember, at 1950 F, there is so much radiant heat that everything is at that temp, with perhaps the only thermal gradiant being from top to bottom in the furnace. My (horizontal) blades are at the same level as the thermocouple, too. Good thinking on your part. I like the horizontal setup, with grooves for my fork cut into the top surface of the firebrick. Eliminates the "Oh ####" factor if you ever bobble a blade with the tongs.

My email is rjmartinknives@comcast.net

I'll put the TTT chart up as a sticky when you send it.

THANKS

Tbonz
11-28-2004, 04:03 PM
I've noticed that there are makers who use ATS 34 for their blades and backsprings and because its been said that 154 CM and ATS 34 are close to being the same I thought it would be OK to use 154 CM as a backspring. Any other opinions on this would be appreciated. THANKS
Tim

RJ Martin
11-28-2004, 05:58 PM
My preference would be for 154CM because in my experience, it is cleaner and has a finer grain size tha ATS34. These elements are key for a spring that won't break.

SteveS
11-28-2004, 07:00 PM
FWIW, I use the same system for S30V as ATS-34/CM-154 and I get about the same results. One thing I did find is that if you get S30V up around 2000 degrees the hardness stays above 60HRC. In fact as I recall more like 61 - no matter where you temper it.

I've posted the information before, but for what ever reason I don't get a rise in hardness after the LN soak with S30V. After quench is about 62 and after LN is 62. Maybe my quench is perfect and no retained austenite? I don't know, but with a temp about 1975 (never can be too sure without good calibration), aluminum quench plates in the packet - S30V isn't a problem for me. (but I don't do anywhere near the quantity of you pros).


Steve

rlinger
11-29-2004, 05:15 AM
RJ,

I will gladly bow to that especially since you back it up with lab testing. I will take the results they gave you as being factual. In addition I do see your and other's opinion along that line of reasoning. One other basis for my belief (or stubborness) is that once upon a time I did some extensive testing on RWL-34. That testing included three different quenching methods, forced air, oil, and plates. My test pieces were about 0.140 inch thick and small in length and width, and flat. The plate quenching produced impressive hardness. Of all quenching methods forced air quenching produced finer grain structure and equal or comparative hardness. All air quenching except for a couple were performed while in foil. Plate quenching was performed while in foil. Oil quenching was performed without foil.

Actually, based entirely on your above posting, I will do a plate quench on one of my own blades and see how it performs. You have convinced me to give it a real time try.

RL

RJ Martin
11-29-2004, 11:05 AM
Steve: Don't worry about not seeing a hardness increase after LN. It means you're doing things right. The benefit is still there!

RL: Hey, give it a try and see. I always try to use common sense backed up by real-life experience. I'm interested in your comments on grain size-How did you measure it (lab analysis or by observation?) I ask because, generally the faster the quench rate, the smaller the grain size assuming equivalent Austenizing temp and soak times. Again, quench plates should do well. You know, you can shoot compressed air in between the plates to really goose the edge, if you like.

R. D. Finch
11-29-2004, 10:07 PM
RJ
When do you place the blade in the furnace? At start are before it reaches a certain temp?

RJ Martin
11-30-2004, 08:24 AM
Ricky: For the first batch of the day, I start with a cold furnace. Some guys keep the furnace at austenizing temp and skip the lower temp soak. I don't like that! For S30V, the soak at 1600 gets the whole piece of steel uniformly energized so it will transform rapidly as the temperature rises. I equate it to warming up before strenuous exercise.
If I'm doing several batches in a day, I will cool the furnace down to about 1200F and start from there, being careful to provide the same amount of time for the furnace to ramp to 1600 that I do when I start with a cold furnace. Below about 1600F, it's easy for the steel to lag the furnace, particularly if you've got a good furnace.

Don Robinson
12-15-2004, 09:28 AM
Don: Actually, I have not received a TTT from Crucible for S30V. I asked for one a while ago, but it wasn't available then. Asking if you can trust Crucible's data is a little like asking if you can trust Alan Greenspan for financial advice. OF COURSE YOU CAN!!!!!!
I heat treat S30V as follows: .

RJ, as I said in a previous post here, I had my first order for a CPMS30V blade.

I used the crucible data sheets, tempered at the low cycle, and everything went perfectly. This was a 3" folder, so I decided to use 61Rc as a final working hardness. And yes, I did cryo quench. ;)

Thanks for your advice. Now i've got about 5 more feet of S30V, so I'll use it more. It's a bear to final finish, though. Used lots of belts and elbow grease. I'll charge a little extra for S30V.

RJ Martin
12-15-2004, 12:48 PM
Don: Yes, that difficulty in finishing is telling you you have a hell of a good blade there!
Glad it worked out for you

Tbonz
01-09-2005, 07:15 PM
I've been tempering at 450 degrees for an hour, twice. I'm shooting for an RC hardness of 58RC to 60RC, does the above tempering procedure seem correct for that goal.
I've notice that some HT procedures call for tempering for two hours twice, would that be a better procedure the doing it for an hour twice?
Thanks
Tim

RJ Martin
01-09-2005, 07:30 PM
Tbonz: Depending on your Austenitizing temp., soak, etc. but, yes, 450F seems about right for that final hardness. Double tempering for 2 hours each is preferable to double tempering for 1 hour each.

Tbonz
01-12-2005, 07:45 AM
the 154 CM blades that I have been tempering at 450 degrees for an hour twice have needed a diamond stone to sharpen them, a regular stone was unable to have much effect at all. Is this to hard?

RJ Martin
01-12-2005, 08:20 AM
Tbonz: Without checking the actual hardness with a Rockwell tester, it's hard to say.
If you're trying to put the initial edge on using stones, I'm not surprised. If you're using an abrasive belt to put the initial edge on, and still having trouble getting the stones to wirk, then you might want to temper at say, 500F and see how this changes your results.

154CM is a wear resistant steel!

mete
01-12-2005, 11:23 AM
Yes , knives are supposed to be sharp and wear resistant !! :)

Tbonz
02-21-2005, 09:00 AM
I have been experimenting with several different HT procedures and I have found the one that works for me. I'm using an EvenHeat Oven, furnace.
This procedure is for 1/8" 154 CM ~ Wrap blade in HT foil and double crimp edges. ~ Into cold oven with edge up ~ Ramp to 1400 degrees and hold 10 minutes. ~ Then ramp to 1900 degrees and hold 10 minutes ~ As quickly as possible remove package and place between two steel quench plates and cool to 125 degrees. ~ Then temper blade in a prewarmed 400 degree oven for two hours, cool to room temperature then repeat at 400 degrees for another two hours.
According to what I've read this will result in a blade with a hardness of RC 58. This procedure was based on information from EvenHeats website supplied by TKS.