Are you over Super Steels?

[SBaker34]

Hi Boris,

A bounty is good. We always like to see what if any problems our knives might have. Can't make them better if we don't know what's wrong with them.

Now that I'm semi-retarded, I'm down to only 40 hours per week, and speaking with our customers is an important part.

sal

Hey you're not that old yet Sal

 

[shqxk]

That broken Para2 was sure a fake... The "S" is obviously difference...

 

[BluntCut MetalWorks]

Yes, Elmax looks nifty good eh. Although I only made 5 cuts/whittles into dried beef rib bone. I should make another 5 cuts and re-imaging...

Am I seeing this right? Being as close up as what it is it looks like there's not much damage. Do you have 52100 photos?

Here is SQ 52100, SQ 1095, D2, M2, 20CV. Be mindful/fair, should take hardness into consideration.

 

[The Mastiff]

Excellent comparison photos Bluntcut! That is a good quench on the 52100 alright. The carbides are seperated pretty well. Contrast that with the D2 where the carbides clump together in places which can cut well in some materials but loses strength and toughness. Still a good HT in the D2 as it's better than many I've seen.

The M2 almost looks like a powder steel. It makes a very good cutlery steel IMO and would be used more if it weren't for powder M4HC steels in use.

I've never seen SQ 1095 but I do see the controlled grain structure and carbides.

To be honest they all look pretty good to me. One can't consistently make good knives without control of the HT and this displays you are doing things properly.

Thanks for putting the images up.

Joe

 

[Chris "Anagarika"]

Bluntcut's 52100 is indeed super steel by the definition offered by some in this thread! :thumbup:

 

[Lycosa]

"semi-retarded."
Sal, I admire your honesty.

 

[Twindog]

Those photos tell a lot. Thanks, Bluntcut.

The 52100 held up really well. I'm surprised by the 20CV. I thought it would do better. It looks carbide rich, though. The "bone test" is a nice counterpart to Anderson's rope tests.

 

[singularity35]

Bluntcut's 52100 is indeed super steel by the definition offered by some in this thread! :thumbup:

I have a kitchen knife that is made from 52100. I slice with it. It's not super thin but it does quite well. It was forged from a ball bearing race and got pretty primitive heat treat but it takes and holds an edge reasonably well.

One time we had some leftover whole roasted pig and somebody(my d**n son) used that knife to chop(bones and all) the remaining roast pig into pieces that would fit in containers to be refrigerated. I was aghast and expected to find humungous edge damage. To my surprise, there wasn't a lot of damage. Nothing I couldn't fix in 10 minutes. That's why 52100 is one of my favorite steels.

 

[B34NS]

Those photos tell a lot. Thanks, Bluntcut.

The 52100 held up really well. I'm surprised by the 20CV. I thought it would do better. It looks carbide rich, though. The "bone test" is a nice counterpart to Anderson's rope tests.

the tradeoff for stainless @ 63HRC I guess.

 

[Cobalt]

Yes, Elmax looks nifty good eh. Although I only made 5 cuts/whittles into dried beef rib bone. I should make another 5 cuts and re-imaging...


Here is SQ 52100, SQ 1095, D2, M2, 20CV. Be mindful/fair, should take hardness into consideration.

Great pics. Looks like 52100 has the best edge so far.

 

[BluntCut MetalWorks]

When a sharp edge (very thin cross section) impacted (forces and combination of into+deflection+twisting+etc..) with non yielding or hard materials (bone, sand, metal, etc..). Naturally, we like to know the state of this edge afterward. As an example, submicron radius apex hits an embedded/inclusion 30um(about half diameter of a hair) grain of sand when whittling wood. This is an impact event (non rolling/adhesive wearing type) and if this type of event is regular occurring, well ideally we can optimally select steels + ht + geometry for most productive result. Of course, I am talking about when percentage of imperfection dent/chip in an active working section of an edge negatively affecting the work result. If not, Bossly voice => 'work harder... stop looking at the edge'

Years ago, I did 3 months raspberry-cane-thinning work (yup, I worked in the berry farm for a handful of years). At that time, I hate the darn billhook (stout version of a mushroom knife) need to resharpen(with a file) every 15-30minutes of work. Rolls & dents were the mode of damage. *time travel* - I will take a knife with more strength & toughness, welcoming microchips anytime anyday. Yeah, I can carry SiC (file like) to sharpen. I cut plenty of rope too and often edge in contact with 3/16" dia wire. Extra wear resistance is obviously would be a nice-to-have after taking care the primary mode of failure.

At some point in chasing ultimate blade per given tasks per given technique/skills, we possibly getting diminishing values in return for investment/effort. It usually mean to last 10-20% of performance. I am not perfecting that last 20% with my ht but hope to expand the 80%.

Excellent comparison photos Bluntcut! That is a good quench on the 52100 alright. The carbides are seperated pretty well. Contrast that with the D2 where the carbides clump together in places which can cut well in some materials but loses strength and toughness. Still a good HT in the D2 as it's better than many I've seen.

The M2 almost looks like a powder steel. It makes a very good cutlery steel IMO and would be used more if it weren't for powder M4HC steels in use.

I've never seen SQ 1095 but I do see the controlled grain structure and carbides.

To be honest they all look pretty good to me. One can't consistently make good knives without control of the HT and this displays you are doing things properly.

Thanks for putting the images up.

Joe

Excellent analysis, thanks Joe!

These edges weren't polished nor etched, so only partial carbides are showing up. D2, some look like grain but actually they are massive CrC (aggregated from mill, which I wasn't to able to break all of them up into smaller carbides).

My SQ (super quench) ht is applicable for low Cr steels (e.g. 10xx, 5160, Cfv, 52100, W2, etc..). SQ is just a super fast quench which would crack/shatter most steels with more than 0.5%(C+N combined). Preparing steels lead to SQ is slightly more important than the hardening quench itself. In turn, w/o SQ these prepared steels won't harden correctly - shallow hardening steels will hit pearlite nose and other deeper hardening steels will suffer some diffusion into grain boundary.

Bluntcut's 52100 is indeed super steel by the definition offered by some in this thread! :thumbup:

Thanks Chris! I am happy with my current low Cr steels ht but with another million$, it could vastly improve. I've a few ht ideas for stainless version of 52100 - gotta make Cr & Mo my ht friends instead of party crashers.

Those photos tell a lot. Thanks, Bluntcut.

The 52100 held up really well. I'm surprised by the 20CV. I thought it would do better. It looks carbide rich, though. The "bone test" is a nice counterpart to Anderson's rope tests.

D2 & 20CV at 63rc shown very low fracture toughness. Look like terrible impact toughness due to crumbly & penetrating fractures.

I have a kitchen knife that is made from 52100. I slice with it. It's not super thin but it does quite well. It was forged from a ball bearing race and got pretty primitive heat treat but it takes and holds an edge reasonably well.

One time we had some leftover whole roasted pig and somebody(my d**n son) used that knife to chop(bones and all) the remaining roast pig into pieces that would fit in containers to be refrigerated. I was aghast and expected to find humungous edge damage. To my surprise, there wasn't a lot of damage. Nothing I couldn't fix in 10 minutes. That's why 52100 is one of my favorite steels.

52100 & W2 (around 1-0.94%C) are very well balance steels. With good ht, it has excellent edge stability and more than enough wear resistance for general usages. There are way to mitigate it lacked of corrosion resistance but can't prevent it.

the tradeoff for stainless @ 63HRC I guess.

Agree. AEB-L/14C28N/Zfinit/similars have good edge stability too. However I need to ht research more (done some), especially dealing some 3-10% of RA.

Great pics. Looks like 52100 has the best edge so far.

Thanks.

 

[SBaker34]

So how would you rank elmax as a general super steel?

 

[bodog]

I thought this was a great post by another member. Explains pretty well how toughness, wear resistance, etc come into play. High wear resistance is kind of useless unless you have some toughness to back it up. Otherwise in real use these "super steels" will dull much quicker due to fracturing at the edge. I just spent the weekend cutting up quadruple layered boxes with pineapples in them, among other things. I used one knife the whole time, the knife Bluntcut sent me to evaluate made of 52100. Normally I'd be resharpening most every other knife I've ever owned, but his still draw cuts paper easily right now. I wish I had a microscope to take pictures of the edge. I'd much rather have an edge that stays intact and blunts slowly through wear than a knife that blunts by simple fracture from impact or from repeated deformation.


.

Hey Drebs. In theory Cruwear should have better edge stability and toughness than CPM M4. Different heat treats can change the steels in a lot of ways including going for maximum toughness. Maximum wear resistance at the expense of less corrosion resistance. Hardness makes the steel stronger but less tough. Add in the fact that in this case the Cruwear mule is ingot while the CPM M4 is powder process and any of the attributes can change putting one ahead or behind the other.

By the steel companies books CPM M4 is ahead in wear resistance and toughness. Corrosion resistance on either one isn't great, but they are far from bad compared to some other steels I've tried that rusted much faster.

Aside from the chrome in both steels the heat treat can make some of the other elements sort of help out with corrosion, or abrasive wear resistance depending on how it ( M4) is heat treated.

3V also has very good edge stability and strength in addition to it's toughness. A lot of people don't understand this when they claim 3V has no place in folders, just large choppers. If the kind of use one has makes the blade microchip instead of other types of failure a higher strength steel can be used. In some cases 3V can have greater wear resistance than higher carbide steels that fail ( get dull) from too little strength though this sort of use in a folder is fairly rare. W2, O1, 1080/84/85, super blue etc. are other steels with good edge stability. Traditionally high carbide fractions which give higher abrasive wear are less strong and tough at the edge where we concern ourselves in this hobby.

Joe

And here is a knife that epitomizes that train of thought. Thin 3V that can probably handle whatever you throw at it, within reason, while not screwing the edge up when you nick a nail or bone or when your encounter silica that's present in a lot of stuff that's harder than the steel itself. Beautifully done and looks super comfortable:

http://www.bladeforums.com/forums/showthread.php/1314276-CPM-3V-SB-Hunter-Utility

 

[bodog]

So how would you rank elmax as a general super steel?

As far as stainless steels are concerned pretty danged high.

 

[Sunyata]

I was watching old football games on TV today and I thought of this thread.


"Are you over sports in HD/UHD/4k? " is how I imagined AV nerd forums would phrase it.


Sure I could watch football on a 20" CRT TV, but progress has made better options

 

[BluntCut MetalWorks]

Added: Super Quenched (SQ) CruforgeV (CFV) 62.5rc, SQ D2 62rc, SQ Elmax 62rc.

SQ Elmax looks very good - some microchips and a long but shallow dent.

* SQ is a hammer, heeellooo steel - you are a nail, aren't you
==============================================================

 

[SBaker34]

I'm amaze at how tough plain 52100 is when heat treated right. I've seen 1095 chip up to and past the bevel from a nail. That looks like it would compete or surpass 3v

 

[BluntCut MetalWorks]

Let's compare impact toughness of the two best edges: SQ 52100 vs SQ Elmax.

** reverse chop: put spine of the blade against concrete, edge straight up. Take a piece of dried beef rib bone (pictured in earlier post), raise about 4" height, strike down. Aim for normal/perpendicular impact. Did 20 strikes, contact area is about 3/8" spread (sorry, I don't have perfect hand eyes coord). Take images of most damage area for each blade using optical microscope at 100x magnifications. **

 

[Cobalt]

I might be wrong, but it looks like 52100 is holding up much better.

 

[SBaker34]

It looks like elmax may have won?