1095 vs Stainless Steel

[knarfeng]

If 1095 is above 60 HRC, say 64 or 65 HRC it will change things quite a bit, but what we gain in edge retention is lost in toughness.

I imagine that to be true, Jim, but most companies don't take it that hard.
IIRC, KaBar runs their 1095 cousin at 57.
Rowen hardens the ESEE knives to 57.
Great Eastern runs theirs at ~58.

 

[Ankerson]

I imagine that to be true, Jim, but most companies don't take it that hard.
IIRC, KaBar runs their 1095 cousin at 57.
Rowen hardens the ESEE knives to 57.
Great Eastern runs theirs at ~58.

I was hinting at something like a custom slicer with a really thin blade around 64 HRC or so could be impressive.

I wouldn't expect the production companies to get anywhere near that hardness, that would be crazy.

Personally I would rather have 10V or K294 if I was going with non stainless, might as well have the best of both worlds.

 

[knarfeng]

I assume you are talking about edge looking better after visual inspection, am I right?

Let straight this out, because when you talk about retention it is actually about how edge looks
under magnification glass. I am using different approach measuring how edge cuts thread on
postal scale - it is much more time consuming but this is I think represents better sharpness of
the blade.

I think this is a key difference leading to different results.

Thanks, Vassili.

I believe the difference in our results is more due to what we are cutting and how. I make slicing cuts in manila rope, which is fairly abrasive. According to Phil Wilson, manila rope does a fair job of duplicating the resistances found in skinning game. Slicing an abrasive medium puts a premium on abrasion resistance, which is why 440C outperforms 1095 in these tests. (It's also why many hunters prefer a carbide forming stainless steel to a non-carbide forming alloy steel or carbon steel. It lasts better in that type of usage.)

In my daily usage of my pocket knives, I find that in whatever cutting I happen to be doing the steel performances I see match the performances I see in my edge retention comparisons. If I were doing other types of cutting, it might not.

 

[2brothers]

What kind of thread for test? Dial or digital scale? Was scale calibrated?

Yes and Kershaw results versus 1095:

Best Kershaw I tested was CPM D2 - 14 th place which is pretty good for Kershaw
Kershaw CPM S30V ZT302 is on 30th place (however Buck 110 with same steel was on 22nd)
Kershaw CPM S110V is only 24th place.
But even worse was Kershaw Elmax - ZT350 hold 32nd place, even behind CPM S30V which is pretty average.

Of course 13C26 from Kershaw hold 40 th place, but it will be hard to expece anything better here
and SG2 from Kershaw is 44 th which is second from the end, but this is pretty same what SGPS shows (41st).

While production 1095 from GEC on 26th place
and of course heat treated by Jody Muller takes 7 th place.

Unfortunately Kershaw is one of companies which does not have CATRA test machine(at leas as far as I know)
and so can not do CATRA testing on what they are doing.

Hope my findings will help.

Thanks, Vassili.

Uh, thanks for answering my questions? WTF?

 

[nozh2002]

Uh, thanks for answering my questions? WTF?

Any time.

 

[nozh2002]

Been using 0551 at work . Elmax reminds me alot of cpms30v but I would say its slighlty better. It is not on same level as xhp and zdp though. That said I don't use till workable edge is gone I use till very sharp edge is gone. I don't use my folders for hard use either.I like my blades very sharp .

I think this consept of "hard use" or using dull knife for long time is just excuse to hide poor performance. 200 cuts of manila rope enough load for every reasonable use and it takes half day to test with some damage to hands. I see no reason to not to re sharpen knife after such load and will not recommend to continue to use dull knife - is it ZDP189 or CPM S30V once it is not sharp, especially for heavy use (again 200 cuts of manila rope more then enough to be names good load - try it)

Let just say that CPM S30V and Elmax gets dull much faster then 1095 and other premium steels and beyond this point nobody should use them.

All my bad cuts or ruined projects happens only because I continue to use dull knives, while I should put them aside or resharpen.

Thanks, Vassili.

 

[hardheart]

Impact absorption and lateral flexibility are quite different.

Toughness measures are for shock loading, or impact testing, it measures when the steel suffers failure.

If powder steels can indeed sustain lateral flexing without failing, why does Crucible(just to name one) forgo publishing data which shows this to be the case?

Because they don't do it for ingot steels, either.

Instead, they notch the reverse side of a powder steel, and then whack it on the opposite side. How practical is that? When will a knife actually be subjected to that in the real world?

That is notched imapct testing and is used across the steel industry. It is considered practical for measuring a property of metals, there is no knife specific testing for toughness.

Although some lateral flex tests are extreme, a knife will more likely be used for prying than notched and whacked in the real world.

That's true for just about every tool, but impact testing isn't done to tools, it's done to metals. Your sledgehammer, screwdriver, prybar, etc probably don't have V, U, or C notches cut in the middle of them, but the steels they are made of were tested by someone using them.

The amount of flex is attributed to the temper. Leaf springs and fillet knives both flex; despite very different geometries. Toughness, or the lack of it, is attributed to hardness; as is edge retention.

No, flex is elastic deformation before the steel yields, and hardness does not determine it. It is the amount of steel you are dealing with, and the amount of load applied.
http://www.bladeforums.com/forums/t...ding-and-busting-steel-quot-demo-Ashokan-2006
there was also a video of this demo, which I will try to find.
Toughness is attributed to hardness, alloy content, environmental conditions, geometry, and heat treat method.

You're saying steel which is not tempered will flex, rather than bend?

Yes, but it depends on how much load you apply to it. Heck, go down to a hardware/home improvement store and flex a piece of flat bar they sell, you can do it easily before causing it to take a set. And also just note that the thicker the piece you flex, the more force you have to apply, and of course the harder it is to permanently bend. All the steel there is unhardened.

 

[Ankerson]

I think this consept of "hard use" or using dull knife for long time is just excuse to hide poor performance. 200 cuts of manila rope enough load for every reasonable use and it takes half day to test with some damage to hands. I see no reason to not to re sharpen knife after such load and will not recommend to continue to use dull knife - is it ZDP189 or CPM S30V once it is not sharp, especially for heavy use (again 200 cuts of manila rope more then enough to be names good load - try it)

Let just say that CPM S30V and Elmax gets dull much faster then 1095 and other premium steels and beyond this point nobody should use them.

All my bad cuts or ruined projects happens only because I continue to use dull knives, while I should put them aside or resharpen.

Thanks, Vassili.

Dunno man, I have made up to 1,000 slicing cuts on 5/8" Manila rope with M390 @ 62 HRC and it still sliced newspaper like nothing, that was a Custom knife, but goes to show what is possible.

200 cuts on 1/2" Manila really isn't enough to dull most steels, might loose some bite, but they will still be sharp.

Almost all the steels I tested were still paper slicing sharp after testing on 5/8" Manila rope, and that's with production knives.

 

[nozh2002]

I believe the difference in our results is more due to what we are cutting and how. I make slicing cuts in manila rope, which is fairly abrasive. According to Phil Wilson, manila rope does a fair job of duplicating the resistances found in skinning game. Slicing an abrasive medium puts a premium on abrasion resistance, which is why 440C outperforms 1095 in these tests. (It's also why many hunters prefer a carbide forming stainless steel to a non-carbide forming alloy steel or carbon steel. It lasts better in that type of usage.)

In my daily usage of my pocket knives, I find that in whatever cutting I happen to be doing the steel performances I see match the performances I see in my edge retention comparisons. If I were doing other types of cutting, it might not.

There is no too much ways to cut manila rope especially 200 times - of course I use slicing motion, of course this is not push cut. I doubt this is the case, until you also use wooden base to damage edge more randomly as it is done on testing shows.

Under magnification glass you may detect only things which are visible under magnification glass. You may see only damage not dulling process.

I did some research under microscope - bought one with x400 magnification and was not able to see difference in freshly
sharpened sharp knife and freshly sharpened dull knife, simple because geometry of very edge is not visible even at x400
so rolled edge and sharp one looks same.

In this terms visible under magnifying glass deformation does not completely represent sharpness because critical state -
very edge angle is not visible.

So it is not really Retention to Dulling, but Retention to micro damages (or not too micro if it is visible under magnifying glass).

Thanks, Vassili.

 

[nozh2002]

Dunno man, I have made up to 1,000 slicing cuts on 5/8" Manila rope with M390 @ 62 HRC and it still sliced newspaper like nothing.

200 cuts on 1/2" Manila really isn't enough to dull most steels, might loose some bite, but they will still be sharp.

Well, to know you need to have sharpness measurement bit more precise then newspaper slicing and sharpness classification
more precise then "loose some bite". It is good for show and commercials for overstocked European Imports, but to talk about
steel performance.

For knife to work not just emergency or casual cuts like delivery boxes - carving leather or wood, cutting roots in the ground
good sharpness is needed, otherwise it will recuire too much force to cut which make it harder to manage and less precise.
In result - it will lead to cuts in the wrong places, too long or too deep etc...

If kinfe can not do work - it is dull, and dangerous - because it is require more power etc, but of coure it is still capable of
cutting paper and unfortunately even more capable of cutting flesh. I learned it after several cuts.

Of course if I chop branches - I do not really care and this can be done with pretty dull knife.

Thanks, Vassili.

 

[Ankerson]

Well, to know you need to have sharpness measurement bit more precise then newspaper slicing and sharpness classification
more precise then "loose some bite". It is good for show and commercials for overstocked European Imports, but to talk about
steel performance.

For knife to work not just emergency or casual cuts like delivery boxes - carving leather or wood, cutting roots in the ground
good sharpness is needed, otherwise it will recuire too much force to cut which make it harder to manage and less precise.
In result - it will lead to cuts in the wrong places, too long or too deep etc...

If kinfe can not do work - it is dull, and dangerous - because it is require more power etc, but of coure it is still capable of
cutting paper and unfortunately even more capable of cutting flesh. I learned it after several cuts.

Of course if I chop branches - I do not really care and this can be done with pretty dull knife.

Thanks, Vassili.

Depends on the steel and hardness.

 

[spydusse]

When I saw elmax is the same category as xhp,zdp and cpm154 in Mr, Ankersons test I expected more then I got . I really wasn't impressed with elmax reminds me more of s30 then any of the other steels in its category . At least she's got a cute smile ..... I guess

 

[Ankerson]

When I saw elmax is the same category as xhp,zdp and cpm154 in Mr, Ankersons test I expected more then I got . I really wasn't impressed with elmax reminds me more of s30 then any of the other steels in its category . At least she's got a cute smile ..... I guess

Results might vary depending on use and the knives used, also the hardness of ELMAX in that one knife, sharpening etc.

I always say my results are not set in stone, but they are the results that I got with the steels and knives I tested.

Keep using it and the results will vary like most other steels depending on use, might be better some days than others depending on what you are cutting that day.

Yes it cuts like S30V, but holds an edge longer than S30V does.

 

[Ankerson]

When I saw elmax is the same category as xhp,zdp and cpm154 in Mr, Ankersons test I expected more then I got . I really wasn't impressed with elmax reminds me more of s30 then any of the other steels in its category . At least she's got a cute smile ..... I guess

You really thinned that edge out didn't you?

That looks to be less than 30 inclusive to me, a lot less.

 

[knarfeng]

There is no too much ways to cut manila rope especially 200 times - of course I use slicing motion, of course this is not push cut. I doubt this is the case, until you also use wooden base to damage edge more randomly as it is done on testing shows.

Under magnification glass you may detect only things which are visible under magnification glass. You may see only damage not dulling process.

I did some research under microscope - bought one with x400 magnification and was not able to see difference in freshly
sharpened sharp knife and freshly sharpened dull knife, simple because geometry of very edge is not visible even at x400
so rolled edge and sharp one looks same.

In this terms visible under magnifying glass deformation does not completely represent sharpness because critical state -
very edge angle is not visible.

So it is not really Retention to Dulling, but Retention to micro damages (or not too micro if it is visible under magnifying glass).

Thanks, Vassili.

The rope is supported by a wooden base. There is a gap in base. I cut over the gap, so the blade only cuts rope.

400x is too high a magnification. It gives too much detail and you can't tell what you are seeing. Next time try a 5x lens. It gives an overall view of the damage. Until you do, you have no idea what I am seeing, so you cannot comment on it.

My results match what I experience in actual use. Moreover, judging by reading a pot-load of posts over the years, they match the average experience of most users. They may not match the experiences of users who perform unusual cutting chores.

 

[nozh2002]

When I saw elmax is the same category as xhp,zdp and cpm154 in Mr, Ankersons test I expected more then I got . I really wasn't impressed with elmax reminds me more of s30 then any of the other steels in its category . At least she's got a cute smile ..... I guess

Well on my test it is exactely same as CPM S30V -

30. Kershaw CPM S30V
31. Spyderco Mule CPM S35VN
32. ZT-350 Elmax

 

[nozh2002]

You really thinned that edge out didn't you?

That looks to be less than 30 inclusive to me, a lot less.

Yea this is I heart before, some people have ability to measure edge angle looking from side of the blade.

Thanks, Vassili.

 

[nozh2002]

The rope is supported by a wooden base. There is a gap in base. I cut over the gap, so the blade only cuts rope.

400x is too high a magnification. It gives too much detail and you can't tell what you are seeing. Next time try a 5x lens. It gives an overall view of the damage. Until you do, you have no idea what I am seeing, so you cannot comment on it.

My results match what I experience in actual use. Moreover, judging by reading a pot-load of posts over the years, they match the average experience of most users. They may not match the experiences of users who perform unusual cutting chores.

I did quite a bit of looking at the edge at x5 as well - and have pretty good idea what are you talking about.
Sorry this is no way to measure sharpness, this is way to measure "visible damage" to the edge, but has little
to do with sharpness caused by usual or unusual cutting.

I can understand that you believe that there is direct connection between visible damage and sharpness, but
bottom line - you are talking about visible damage, I think people should understand that. While I am talking
about statistical results - median from 21 cuts of cotton thread on postal scales with controlled (by metronom)
pressure increase... See my old video (without metronom yet (there is microscope there in the background)).

http://www.youtube.com/watch?v=1Ftbus7LbtU

Now I am not sure why you pushing idea that my manila rope cutting somehow different then yours. Can you
explain that?

Thanks, Vassili.

 

[Bill1170]

It always comes to this: http://www.youtube.com/watch?v=kQFKtI6gn9Y

 

[Ankerson]

Yea this is I heart before, some people have ability to measure edge angle looking from side of the blade.

Thanks, Vassili.

Well when you test the exact same model knife and reprofile it to a measured 30 degrees inclusive you can be a really good guesser.