Is 154cm the same as ats34 ?

Keep in mind that the high-end knife market is a very small niche market. I would not hesitate to guess that high-end knives as a whole use less steel per year than is used on a single jumbo jet aircraft.

Small-batch, what one might call "Boutique steel," is Crucible's claim to fame. They are tooled to economically make products that the big-boys just can't economically touch. But development costs are still what they are and Crucible can't react to everything.

They also need to keep in mind how an alloy fits into their product line as a whole for the broader market. S30V finds uses other than knives. Those other uses push up the volume on S30V enabling Crucible to economically keep S30V in production.
 
If you want something similar to INFI, buy Chipper Knife steel from any tool steel supplier.

Some clarification on the comments maded on these elements.

Originally posted by Dalko.

Talking about 3V, I would like to know why it doesn't have Nickel (adds toughness), Cobalt (to strengthen the steel matrix) and Nitrogen (to form nitrites that allows high wear resistance while not decreasing toughness).

Nickel does not add toughness. It promotes through hardness and is added for heat treat response in lower alloy iron based materials.
Cobalt does not strengthen the steell matrix, it actually hurts toughness. Cobalt is added to improve resistance to hardness loss from heat. If you see it in a material it is there so the material can resist high temperature applications. In stainless steels it is for bearings.
Nitrogen will not form nitrides unless forced to do so and only on the surface. What nitrogen does is substitute for carbon without tying up other elements. In stainless steels this means attaining high hardness without reducing the chromium content thus keeping corrosion resistance high. In non-stainless steels it increases hardness without forming carbides thus keeping the toughness up.

I normally would not correct the statement above but it was so far off, I was afraid someone might think it was true. If you wonder how I know this, I'm one of those scary metallurgists.
 
Different makers make knives for different reasons.A great maker like Buster Warenski uses a lot of 440c along with many high end makers.Maybe its cause of the finish of the steel and low maintinence.I do'nt know but he feels its the best for the knife he's making.At thousands of $ a knife I do'nt think price is a factor in his decision.I do'nt think most of his knives will even see any cutting work.BTW I do'nt think most of the people on this forum can seriously tell the difference between 440c,ATS34,154cm,S30 or many of the other high end steels,if they were given similar knives with no markings on them :eek:
 
Dalko said:
-------------------------------------------------------------Talking about 3V, I would like to know why it doesn't have Nickel (adds toughness), Cobalt (to strengthen the steel matrix) and Nitrogen (to form nitrites that allows high wear resistance while not decreasing toughness)."



CPM steels are reputed to have nitrogen, as a trade secret. It is used with Carbon to form CarboNitrides with the transition metals. eg. VCN.

Certainly no steel manufacturer would be interesrted in having Nitrites in steel. A nitrite is a partially oxidized anion (NO2-)that cannot exist there.
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The nitrogen is not a trade secret. It is put into S30V strictly to keep the attainable hardness up without hurting the corrosion resistance. Many stainless steels contain nitrogen. It is a common practice in steel making. It amazes me how much mis-information regarding steel is floating around.
 
shgeo said:
CPM steels are reputed to have nitrogen, as a trade secret.
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It's not exactly a trade secret. Mr. Barber was asked that very question. He explained that the particle metalurgy process consists (and I'm summarizing my understanding here) of pouring the liquid molten steel into a jet of nitrogen which blows it into tiny beads called particles which solidify almost instantly. He had a bottle of them and passed it around and they are like corse sand. This results in a different crystal structure than would be obtained by pouring the steel into a form and allowing it to cool slowly. Large billets of steel poured in forms can take days to cool and solidify just because of their mass. The problem, of course, is that the result is not a large, solid piece. Unless you're into very, very miniature knives, the particles aren't much use. So, the particles are then put into a form and then heated under pressure and essentially forge welded (much as is done when Damascus steel is made) into a solid piece. Because the temperature used to fuse the particles into a solid piece is less than that needed to melt it into a free-flowing liquid, the desired crystal structure is not disturbed.

All of this is done in a nitrogen environment to avoid oxidation. Especially the pouring of the liquid steel into the nitrogen jet, some nitrogen is absorbed by the steel and remains in it. And that is not a bad thing.
 
Satrang said:
It is a common practice in steel making. It amazes me how much mis-information regarding steel is floating around.
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Which is why I was so happy that Crucible gave that wonderful talk at the Oregon show. It cleared up so much for me.
 
Larrin said:
Your reports of corrosion resistance, in my opinion, are another result of hype. When it comes to the composition of both, 3V should at least be just as good at corrosion resistance.
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Cliff Stamp has done salt water soak testing with INFI and it just surface rusted where as some so-called stainless steel like ATS-34 deeply pitted.

3V is recognized as very prone to deep pitting, every knifemaker that uses 3V I talked to told me that.
 
Larrin said:
This is probably one of the dumbest things I've ever read. INFI is famous? Maybe on this little forum, in your little Busse world.
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:eek: Go get him! :D
 
Satrang said:
Nickel does not add toughness. It promotes through hardness and is added for heat treat response in lower alloy iron based materials.
Cobalt does not strengthen the steell matrix, it actually hurts toughness. Cobalt is added to improve resistance to hardness loss from heat. If you see it in a material it is there so the material can resist high temperature applications. In stainless steels it is for bearings.
Nitrogen will not form nitrides unless forced to do so and only on the surface. What nitrogen does is substitute for carbon without tying up other elements. In stainless steels this means attaining high hardness without reducing the chromium content thus keeping corrosion resistance high. In non-stainless steels it increases hardness without forming carbides thus keeping the toughness up.

I normally would not correct the statement above but it was so far off, I was afraid someone might think it was true. If you wonder how I know this, I'm one of those scary metallurgists.
Click to expand...


Well, IF Nickel doesn't improve toughness and IF cobalt doesn't improve the strength and IF nitrogen doesn't form nitrites, I guess those websites are giving a lot of misinformation, which I think is not the case.

http://www.spyderco.com/edge-u-cation/steel.php

http://www.primosknives.com/articles/alloys.htm

http://www.pvsteel.com/docs/Tsb-125.pdf

http://www.knifenetwork.com/workshop/tut_alloy_primos.shtml

http://www.materialsengineer.com/E-Alloying-Steels.htm

http://www.atar.com/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=21&MMN_position=29:21


BTW Satrang, before replying me and throwing me some $hit as it is the tendancy on this forum, please take the time to read what it's written in the pages I provided to you.


Also, I normally would not correct the statement above but it was so far off, I was afraid someone might think it was true. :D
 
Dalko said:
Cliff Stamp has done salt water soak testing with INFI and it just surface rusted where as some so-called stainless steel like ATS-34 deeply pitted.

3V is recognized as very prone to deep pitting, every knifemaker that uses 3V I talked to told me that.
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This couldn't possibly be true. The main alloy used in knife steels to prevent pitting is molybdenum, which ATS-34 has 4% of, more than any other commonly used knife steel (in fact, more than any steel that I know of).

What knife makers have you talked to?
 
Larrin said:
What knife makers have you talked to?
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Don't have all their names off hand, but Hossom was one of those. I usually take what Hossom says about steels with a BIG grain of salt, but knowing and explaining how a steel rusts is just a matter of observing the steel rusting through usage and Hossom has been using 3V for a while and therefore has had the opportunity to see it rusting.
 
Dalko said:
I usually take what Hossom says about steels with a BIG grain of salt
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What part of your background, other than reading the internet, makes you more of an expert than Jerry?

How much metallurgy experience do you have?

How much testing have you done?

How many steels have you tested?

How many knives have you tested?

How many steels were represented in the knives you tested?

Do you actually own a knife?
 
You guys are funny :D


440c, ats-34, and 154cm are all really great blade steels. They have all been around for a long time and buyers are familiar with them. They take a better finish with less effort than s30v and have a higher degree of stain resisitance.


s30v is still the new kid on the block. Alot of makers and thier customers are still uninformed about it's properties. As has been proved by this thread there are still alot of myths floating around about this new steel.
 
Since I'm being quoted out of context I'd better clarify what Dalko thinks he remembers. 3V has about the same corrosion resistance as D2. It can be improved by etching the finished surface to remove oxide contaminants, the source of pitting unless they are addressed. What I did say is that WHEN it rusts, it is usually as deep pits rather than an even surface bloom as you see with tool steels. I have never said it rusts easily; it doesn't. The better the finish, the less prone 3V is to corrosion and because it is incredibly fine grained it can be given an extremely fine finish. Obviously, the easiest way to deal with rust is a little oil.

I should point out that when Devin Thomas made a damascus from CPM-3V and 154CM, I had a VERY difficult time differentially etching those steels. Both resisted Ferric Chloride and Muriatic Acid (30% HCl) etches like nothing I've ever seen. The 3V refused to rust, and I finally had to polish the blade to clearly display the two steels in the pattern.

Back on topic, I use a lot of 154CM. It's a great steel. S30V is better in every respect, including corrosion resistance. No myths involved.
 
Dalko, Time to fling some $hit.

The references you show are all right in some respects but still are too vague as is the case of many "generic" references. I've balanced alloys for a living and will give you one specific case of where verbage is off and misleading.

Cobalt: On Spyderco's reference it states "Increases strength and hardness"
let me explain, in detail, what is really going on. Cobalt is a solid solution element which means it does not combine with other elements. Thus, when say 10% cobalt is added to a 1% carbon iron alloy, the matrix goes from 99% iron to 89% iron. An iron matrix with 89% iron 1% carbon will have a higher attainable hardness than the non-cobalt alloy. The strength term is often the general term for Tensile strength. Tensile strength and hardness are identical in heat treatable alloys thus "strength" goes up with cobalt content. Impact strength another form of strength goes down with cobalt content.
Now I could elaborate on the direct substitution of nitrogen and carbon without forming nitrides and explain why nickel does improve the strength of Ferrite but has little effect on Martensite but how much $hit can one shovel in a night?
 
Gollnick said:
So, the particles are then put into a form and then heated under pressure and essentially forge welded (much as is done when Damascus steel is made) into a solid piece. Because the temperature used to fuse the particles into a solid piece is less than that needed to melt it into a free-flowing liquid, the desired crystal structure is not disturbed.
Click to expand...

I am pretty sure that is a sintering process, essentially identical to the firing of ceramic. The high surface energy of the small spheres provides the necessary energy to have a "melting" process below the actual melting point. The pressure is added often to keep the little particles together when forming the final form (blank) and reduces the required heat for the sintering process. Often the pressure also improves the "grain growth" of the sintering process (different from the grains of the crystal structure). Gollnick, does that sound about right?

Satrang, any corrections? Feel free to correct me if I am wrong. I deal a lot with surfaces but very little with metalls.
 
because I asked the Crucible Metallurgist specifically 3 years ago, after Ed had left them if CPM was similar to sintering, and they said no. Their process is specific to the Crucible Particle Metal process, and not sintering. Diffierent not to be similar was what they told me.

Best Regards,

STeven Garsson
 
But I want to know, this thread needs to cool down a bit I think, but contains lots of great info: My understanding is that Ni will distort the Ferrite matrix because it is larger than Fe, and substitutes for the Fe atomes in the lattice, but in large amounts it increases the solubility of C (like in 18-8) and prevents the transition from austenite to martensite which essentially reduces (or as in 18-8 eliminates) hardenability. In small amounts it should reduce the necessity for tempering and increase toughness to some degree? And N is one of the very few elements (like C) that actually fit into the interstitial space in the Fe lattice but not without distorting the lattice which should increase hardness similar to C.

What I don't get is how such a little amount N as in H-1 (0.1%) can make such a big difference if you need roughly 0.8% of C to attain max. hardenability? Or is the role of N in H-1 simply overrated and the Si which should form the bulk of the preciptate is the clue here. At the amount of Ni H-1 should be pretty much unhardenable by a austenite to martensite conversion? So many questions. I understand that the last paragraph is overly simplified and a long shot, but anybody up to help to lift the fog? Satrang?
 
Controversy was raised again!

It's nearly impossible to talk without figthing and since I do not have anywhere near the patience to deal with figths like Cliff does, I will not reply anymore here. I'm not interested anymore in pissing contests that never end.

BTW, when I asked my questions, I clearly stated they were addressed to Conan and that meant I wasn't interested in other people's answers. If I could, I would have written him a PM or an email, but when I try to PM someone, the system tells me I'm not allowed to do so.

Finally Jerry, I never said that you'd said 3V rusts easily, I said you'd said that when 3V rusts, it deep pits. you came here just to repeat that!

What is so funny here, is that we have Jason saying 440C, 154CM and ATS-34 have a higher degree of stain resisitance than S30V and the following post is Hossom saying that S30V has more corrosion resistance than 440C and ...

Even knifemakers don't agree between each other!
 
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