Matrix Steels K888 and CPM 1V - Age of the Hyper Steel?
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- เผยแพร่เมื่อ 28 มิ.ย. 2024
- Bohler released a new non-stainless powder metallurgy steel called K888 which is advertised as having extremely high toughness even at hardness levels of 64 Rc. I tested it as well as the very similar, older CPM-1V to see how they compare with other knife steels.
Written article for this information: knifesteelnerds.com/2024/03/1...
00:00 Intro and History
03:33 Advertised Properties
04:33 Microstructure
06:03 Hardness and Heat Treatment
09:02 Toughness
14:03 Edge Retention
16:01 Summary and Thank Yous
6:32 a lot of patience went into making those graphs!
You make understanding this not only easy, but enjoyable. You truly are a pillarmen of the community!
thank you Larrin you put your heart and soul into your work and it shows thank you for all that you do
Thanks for all you do Larrin, you're an invaluable resource and wealth of knowledge for this community.
Thank you Larrin, Roman, & Shawn! You all are an invaluable resource!
Most of the thanks here deserves Larrin I think - because of that tempering curve. That one surely took a while to make!! I merely ground down a block of K888 and sent it to Larrin.
Thank you for the impact you have had on this community. I have read your book and bore my coworkers with your videos while I work. Keep up the good work!
Please also provide updated toughness - edge retention charts. Thank you.
Can you please make an excursion Video into sword steels (war knifes?)? I'd really like your take as a high level steel expert on what would be a good (or the best) modern choice for sword blades. Maybe even whether you think blunt training blades have a different ideal to sharp blades.
I do appreciate how much work went into this analysis, an I have bought and read your (first?) Book about knife steels and knife design. I would be interested in you oppinion on sword steel, precicely because I think so highly of your work
I'm guessing 8670 I've seen it do alot of damage to other steels.
Larrin deserves steel sainthood
Wow! Thanks for the effort that goes into something like this.
Well, Z-Tuff remains the king of the hill it seems. Thanks for testing Larrin!
Very interesting video with lots of time invested! Way to go Larrin!
Thank you for all you do, Larrin. The depth of information you provide is invaluable. Your efforts are greatly appreciated.
Ty good sir. Your contributions are invaluable
Very Cool!!!! Love All your videos!!!!
Roman is the best. I have his shards in Nitrobe 77 and Vancron SC
I'll always be shocked to see how badly 1095 performs compared to all those other steels. I don't see the point of using hypereutectoid steels, they just seem to sacrifice toughness a lot, just for a bit more wear resistance (but in that case, wouldn't a lower carbon steel quenched and tempered but left hard outperform in pretty much all ways a very high carbon steel quenched and tempered to a lower hardness ?)
Thanks a lot for your fantastic work larrin !
Yeah, that's basically how it works. 1095 can be done better if you do a lot of care with proper spherodized carbides and proper carbon dissolution, small grain size, and some such. One can also do a marquench/interrupted quench for higher toughness. But yeah, the iron carbides do very little for actual wear resistance even compared to just running eustectic steel harder.
Lot in there which probably makes for a good drill bit or machine cutter, weighing up the cost and the processing time of them for a knife blade?
I'm going with 'maybe', if someone needs it then they're going to want it but the cost might get rid of a lot of the riff-raff!
Before you know it there will be companies forging in space. Maybe with a name like "0G-CPM1 Ultima steel". "Forged in Zero Gravity at the heart of a star" lol
Jokes aside though. Very informative & well laid out content. I enjoy it very much.
Zero gravity knife forging would be wild to see 😂
So in short we are not quite at the age of hyper steels, but if anything were to be considered a hyper steel it'd actually be ZTuff and not K888
Thank you Larrin!
You are a doing Gods work. I’m going to join your patreon.
Interesting! Big thank you to my three steel saints 🙏😇
Great video, even to a dummy like me! You are one of the best at making it make sense! Thank you for doing what you do!
Calling 1v a "hyper steel" reminds me of the old "what will happen to Maxamet now that Vtoku2 is out?" post on BF or the Spyderco forum.
A real good question that needs to be answered is:
What constitutes a "hyper steel"? 🤔
To me, when I think of the term "hyper steel", I think of insane edge retention on par or surpassing edge retention ratings (according to Larrin's score chart) of Maxamet (11) and Rex 121 (12), along with having increased toughness at a 6 or above (Maxamet and Rex 121 score 2 and 1 respectively for toughness, and of course having solid corrosion resistance at 7 or above (The two steels above rating at 4.5 and 3.5).
Plainly put, "hyper steel" sounds like the fictional/magical realm of "Adamantium", "Vibranium", "Uru", "Valyrian", "Mithril", "Adamantine", or "Vorpal".
Maybe, Larrin and the sciences, can work some "magic" and bring about some of these fictional steels to life....Of course, Spyderco will be the first on line to make use of it for the blade community!😉
It’s probably best if this “hyper steel” term doesn’t catch on
@@KnifeSteelNerds Humans love mental shortcuts and symbology. Life is very easy in black and white. Many folks are just fine living a flat, two dimension, smooth, black and white life. Much of this is mediated by intelligence. The less of it you have the more effort it takes to see life in "3D" the more of it you have the more effortless and natural it is. Endless nuance, endless "wrinkles."
Sadly the hyper steel term is already floating around lol.
So, hype, not hyper
it's always hype. everyone with at least two brain cells to rub together should immediately know that just in life.
@@user-xf4es7eh9y MagnaCut was hyped and proved solid as advertised. Maybe I just have more than two brain cells, so what do I know.
@@JoeBusic Magnacut did something genuinly new and occupied a new area of hardness / toughness / corrosion resistance balance, which was unoccupied before. The 888 seems excellent for its intended use-case as a HSS. But unless you want to use your knife as a branding iron, it doesn't really make sense as a knife steel imho.
@@JoeBusicagreed as well as ApexUltra having a much better edge retention while being forgeable carbon steel.
My old favorite tough steel, 3V, shows equal or better toughness than 1V while beating it at wear resistance.
Great video as usual! I only have one knife in CPM-1V. It’s a Bark River machete. I’ve been impressed with its toughness. I have abused that machete like a rented mule. I have not had to sharpen it yet so I can’t speak to its ease of maintenance. It certainly seems to have good edge holding ability. Maybe on par with A2?
I'm kinda most shocked looking at that edge retention graph.
I didn't expect O1 to be particularly high but was more surprised how relatively cheap stainless steels outperform carbon steels.
All this time I was under the impression that A2, O1, 52100 etc would hold an edge better than 14c28n, aebl, 440c etc
440C has the same carbon content as A2, O1, and 52100 but with much higher chromium. That higher chromium means the formation of harder chromium carbides that contribute to wear resistance. If at the same hardness the 440C resists edge wear better.
Bohler often recommends 3 tempers when over 900f.
From the brochure
Three tempering cycles between 530 °C and 570 °C (986 °F and 1058 °F) are recommended.
Impressive, but not enough to be worthy of being called a "hyper steel".
I think Larrin will be the one to bring us a true hyper steel! Magnacut for me, has been an outstanding all-around stainless super steel - so I can't wait for Larrin's next impressive iterations of steels!
Thanks for the fine work Larrin!
Magnacut with a nickel addition probably would lead to a true hyper steel, might have to drop the carbon down to .8 or something though.
@@hoppeanofasgard1365
Maybe Larrin's got a new mix for Magnacut 2.0, so we shall see....
I’m getting into knife making, after watching some of your videos I just ordered your book today off amzn. Is it possible you do a video on the proper heat treating steps, I notice you have a video on heat treating w/ a forge. Fortunately I’m in the position to get quality tools and plan on use of a furnace. I’m convinced heat treating correctly is the most critical step in knife making.
I will see what I can do
What applications, if you were anchor the points like a behaviorally anchored rating scale, would be best for different Toughness and Hardness?
Long Live Science!
Thank you for doing all this research. One question how long do you temper for two hours?
My wife is looking at me thinking, "Man crush much?" :)
How does 1v comp to cruwear in terms of corrosion resistance? As a southerner I enjoy cruwear for it's near stainless quality while retaining good edge retention and strength.
CPM-CruWear would be better with its higher chromium
I'm excited to see how CPM 1V performs as a knife especially a fixed blade. I have a Cruwear Manix XL and I've absolutely loved the toughness to edge retention ratio I seem to be getting out of it but 1V seems like it would be a decent upgrade especially on a fixed blade. I'd like to see something scandi ground with 1V as the added toughness should help with the strength of the edge.
there will be a loss in edge retention with 1v compared to cruwear, but if you're going for a chopper type blade this shouldn't matter much especially at hrc 63 or above.
Added toughness does not equal greater strength at the edge. Greater strength and hardness leads to greater edge stability or strength.
Toughness means less likely to chip, it'll roll instead, but it doesn't mean it'll have greater edge stability and strength. You need hardness and fine grain for that.
@@topfueljunkie100 agreed, that's why I said maybe only if it's a chopper where the main mode of failure would be chipping from impact.
It would be a terrible choice for a folder or even smaller survival knives.
@@hoppeanofasgard1365 For sure. My comment was intended to be directed toward the OP and the final sentence of his original comment. I wish it'd automatically tag the OP like it does for subsequent comments I reply to though, so I get how it can look like I was responding to you. I should have specified though. But I agree with everything you've said.
I certainly like the idea of a tough chopper blade that's able to maintain a higher Rc and thus a better, more stable edge!
What types of knives do you think K888 will be ideal for? Fixed blades \ hard use? Hard use folders?
Thanks for the video!
PS: I am growing more fond of Magnacut with use, it is my go-to in stainless blade steel. (Fishing in saltwater)
So, what steel would you say is a good choice for long term knife use across many decades of daily use? I'd predict all of them are fine as long as you care for them properly
Do you know if it would be possible to get Damascus with these type of metals?
I need an advice, and it might create a hot debate. But please, remain polite and friendly. I understand each one has its own preferences and it's ok like that.
I'm looking to buy a GOOD Bushcraft knife and I'd like to have your opinion on that. Here are the specs I'm looking for.
GRIND:
Scandi because I'm not a real pro at sharpening.
EDGE RETENTION:
Important, but not critical. I prefer a good blade with less chances to break. So to have to sharpen more often is not a big deal. However, I don't want to have to sharpen it every minute. you see what I mean.
LENGTH:
Most Bushcraft knives are around 4.5". Which is not great, in my opinion, for batoning a 5" blade would be nicer.
TIP:
I prefer a flat tip over the tanto types like the SK-5. This for batoning's reason.
RAT / FULL TANG
Full tang of course.
STEEL
Big question! I want one that I can make feathersticks, small carving, batoning, etc.. It's a bushcraft utility knife and not a survival knife (I'd choose a much bigger knife for survival).
Thanks for sharing your input on that!
P.S. Please no Bear Grylls or Pathfinder's stuff ;)
man these videos are incredible. Demystifying a lot of of the blah blah about these steels
I have a zdp189 knife that’s sharper than razor blades. What super steel should I seek next?
Do you publish these in peer review literarture?
No. I have thought above publishing on CATRA or Pattern-welded Damascus or something but haven’t done it
Kate 88...that's what I'm calling it
Could the cut direction on K888 somewhat influence its toughness measurements?
Bohler cross roles to the end, so it shouldn't matter.
There was no mention either in this video or in the article on how were K888 samples obtained and we doubt they were cut from sheet stock.
@@sabolbrothers Well, good thing It was sent to a PhD Metallurgist. 👍 All taken care of.
The direction can matter even with cross rolling because the rolling is never perfectly even in every direction. These K888 toughness coupons broke in the “normal” direction, or thickness direction. The “weak” direction is when the crack grows along the rolling direction, called transverse toughness.
@@KnifeSteelNerds So, was the K888 cut from sheet or bar and in what direction?
I don’t think there’s enough improvement to justify a whole new classification of hypersteel
At least that’s what ztuff said
Yeah let’s stop making up new dumb terms like “hyper steel”
I have knives in 1095, 1070something, d2, m390, 154CM, 440c which is poop and an old file I turned into a wood working knife
Too bad my favorite steel (magnacut) is not on any of the charts to compare to... 😢
of course a steel company has instagram
I'm interested in your opinion on the problems with magnacut steel
Hyper steel and super steel is a very subjective term. Pretty much all modern powdered steel (or PESR or whatever else advanced process) is pushing the limits of material science, it really depends what you're using it for or what you want out of a steel.
We probably don’t need either term
Let's be real, it's always hype. but folks love living life on the naive side with everything. from consumer awareness to politics to dating and everything else.
I will stay with MagnaCut and Infi.
Why don't we make an awesome steel melt it all together then go and use a bastard file shave it down to nothing take the shavings and compress that together to make even finer metal flakes