K390 and S110V Discussion Thread
- senorsquare
- Member
- Posts: 1531
- Joined: Fri Nov 02, 2012 8:34 am
- Location: Lotta Rock, AR
K390 and S110V Discussion Thread
Thought I would start a thread to discuss these two steels that spyderco has so kindly graced us with. Does anyone in the know care to talk about wear resistance, toughness, corrosion resistance and any other relevant properties of these steels? Please share.
sir_mike wrote:Good idea on the thread cause I would like someone to comment on these steels compared the the green PM2 cts-204p.
How would this new Native compare to the green PM2?
Thanks in advance for any comments/info. :D
I'd say that they're pretty similar in the extended lead times jams up online ordering systems :)
Can't say until I get my S110V and try it against M390 and 20CP.
Click here to zoom: Under the Microscope
Manix2, Elmax MT13, M4 Manix2, ZDP Caly Jr, SB Caly3.5, Cruwear MT12, XHP MT16, South Fork, SB Caly3, 20CP Para2, Military Left Hand, Perrin PPT, Squeak, Manix 83mm, Swick3, Lil' Temperance, VG10 Jester, Dfly2 Salt, Tasman Salt
Chris
Manix2, Elmax MT13, M4 Manix2, ZDP Caly Jr, SB Caly3.5, Cruwear MT12, XHP MT16, South Fork, SB Caly3, 20CP Para2, Military Left Hand, Perrin PPT, Squeak, Manix 83mm, Swick3, Lil' Temperance, VG10 Jester, Dfly2 Salt, Tasman Salt
Chris
-
- Member
- Posts: 619
- Joined: Sat Feb 09, 2013 12:54 pm
-
- Member
- Posts: 3852
- Joined: Sat Dec 31, 2005 2:23 pm
- Location: Earth
- Contact:
A few points :
-it isn't the hardness it is the microstructure that is critical
-the same hardness with different microstructures will have more of a difference than from steel-to-steel
-k390 is designed to have a hot hardness improvement over k294 (A11 / 10V)
-that is why it has reduced Vanadium and increased molybdenum and tungsten (vanadium is very poor at secondary hardening because it is so temperature stable)
-the cobalt acts as an austenite stabilizer for the same reason (and keeps out ferrite which will start to become a problem as the alloy content in solution goes up as they are ferrite stabilizers)
-the materials data for all of these steels is available, and I mean the materials tests not the marketing sheets
-S110V has the same abrasive wear resistance as 10V
-S90V is lightly less
-the difference in how each is hardened (not the hardness) makes more of a difference than if it is S90V vs 10V vs S110V
-the differences are also so small that even small angles / grit changes would be larger than the steel influences
-they all have large carbide aggregates due to the huge carbide volumes (on the order of 10 microns)
They are all :
-extremely wear resistant
-very difficult to grind
-low edge stability
-extremely low sharpness edge retention in abrasive materials
I have for example S110V from R. J. Martin and S90V (and 10V) from Phil Wilson, it would be very difficult to separate them, you would need to have a precision of 5% or less and good luck with trying to achieve that by hand. This would mean that your :
-cutting speed
-force
-angle/attack approaches
-sharpening angle/grit finish
-material consistency
Were all reduced to under 1% each as they all have to add up to less than 5%.
In short if you like how high carbide steels behave you will like these but you are very unlikely to be able to separate them assuming sensible HT on each.
-it isn't the hardness it is the microstructure that is critical
-the same hardness with different microstructures will have more of a difference than from steel-to-steel
-k390 is designed to have a hot hardness improvement over k294 (A11 / 10V)
-that is why it has reduced Vanadium and increased molybdenum and tungsten (vanadium is very poor at secondary hardening because it is so temperature stable)
-the cobalt acts as an austenite stabilizer for the same reason (and keeps out ferrite which will start to become a problem as the alloy content in solution goes up as they are ferrite stabilizers)
-the materials data for all of these steels is available, and I mean the materials tests not the marketing sheets
-S110V has the same abrasive wear resistance as 10V
-S90V is lightly less
-the difference in how each is hardened (not the hardness) makes more of a difference than if it is S90V vs 10V vs S110V
-the differences are also so small that even small angles / grit changes would be larger than the steel influences
-they all have large carbide aggregates due to the huge carbide volumes (on the order of 10 microns)
They are all :
-extremely wear resistant
-very difficult to grind
-low edge stability
-extremely low sharpness edge retention in abrasive materials
I have for example S110V from R. J. Martin and S90V (and 10V) from Phil Wilson, it would be very difficult to separate them, you would need to have a precision of 5% or less and good luck with trying to achieve that by hand. This would mean that your :
-cutting speed
-force
-angle/attack approaches
-sharpening angle/grit finish
-material consistency
Were all reduced to under 1% each as they all have to add up to less than 5%.
In short if you like how high carbide steels behave you will like these but you are very unlikely to be able to separate them assuming sensible HT on each.
-
- Member
- Posts: 750
- Joined: Fri Apr 20, 2012 11:06 pm
- Location: Denver, CO
Cliff I would just like to say thank you for the knowledge you contribute to this forum in a manner that is easy for the average person to understand and unbiased, just the facts. THANK YOU!
Current :spyder: : Para2's Brown, Blue & Orange, Etched Spin, CF Caly3 ZDP189, Gayle Bradley, UKPK Orange G10, Manix2 M4, Sage 1, Caly 3.5 in Super Blue, Urban Orange G10
gbelleh wrote:I'm mostly concerned with knowing more about corrosion resistance, as I'm sure the cutting performance of each of these will far surpass my needs.
http://www.crucible.com/PDFs%5CDataShee ... v12010.pdf
According to Crucible S110V has higher corrosion resistance than 440C or S90V
We will have to wait and see what the final hardness ranges are...
I have tested K294, CPM 10V (A11) and S110V all at high hardness (64 for K294, 64.5 10V and 63.5 and 65 for S110V) and there is a difference between A11 and S110V.
But those are all customs ground very thin behind the edge...
Will have to see how the Mule in K390 does as it's a production knife against the other production blades in S90V that I have already tested.
Didn't get the forum knife in S110V, have the CF Native 5 on preorder, but the Native 5's blade is too short to test so will have to wait for a larger blade from Spyderco at a later date hopefully a Military or Para 2.
I have tested K294, CPM 10V (A11) and S110V all at high hardness (64 for K294, 64.5 10V and 63.5 and 65 for S110V) and there is a difference between A11 and S110V.
But those are all customs ground very thin behind the edge...
Will have to see how the Mule in K390 does as it's a production knife against the other production blades in S90V that I have already tested.
Didn't get the forum knife in S110V, have the CF Native 5 on preorder, but the Native 5's blade is too short to test so will have to wait for a larger blade from Spyderco at a later date hopefully a Military or Para 2.
Would it be a good idea to do a regrind on either / both knives to get very thin behind the edge?Ankerson wrote:We will have to wait and see what the final hardness ranges are...
I have tested K294, CPM 10V (A11) and S110V all at high hardness (64 for K294, 64.5 10V and 63.5 and 65 for S110V) and there is a difference between A11 and S110V.
But those are all customs ground very thin behind the edge...
Will have to see how the Mule in K390 does as it's a production knife against the other production blades in S90V that I have already tested.
Didn't get the forum knife in S110V, have the CF Native 5 on preorder, but the Native 5's blade is too short to test so will have to wait for a larger blade from Spyderco at a later date hopefully a Military or Para 2.
That will improve performance most defiantly, depends on what you would want.md8232 wrote:Would it be a good idea to do a regrind on either / both knives to get very thin behind the edge?
Get them down to around .010" to .015" behind the edge or so.
Would have to watch the side loading after that though.
Or maybe a Mule...but probably not, different bladestock...Ankerson wrote:We will have to wait and see what the final hardness ranges are...
I have tested K294, CPM 10V (A11) and S110V all at high hardness (64 for K294, 64.5 10V and 63.5 and 65 for S110V) and there is a difference between A11 and S110V.
But those are all customs ground very thin behind the edge...
Will have to see how the Mule in K390 does as it's a production knife against the other production blades in S90V that I have already tested.
Didn't get the forum knife in S110V, have the CF Native 5 on preorder, but the Native 5's blade is too short to test so will have to wait for a larger blade from Spyderco at a later date hopefully a Military or Para 2.
Cliff, what do you mean by 'low edge stability'? Do you mean the edge is easy to chip, loses its sharpness very quickly or what? Thanks.Cliff Stamp wrote:
They are all :
-extremely wear resistant
-very difficult to grind
-low edge stability
-extremely low sharpness edge retention in abrasive materials
-
- Member
- Posts: 3852
- Joined: Sat Dec 31, 2005 2:23 pm
- Location: Earth
- Contact:
Basically Yes and Yes.bchan wrote:Cliff, what do you mean by 'low edge stability'? Do you mean the edge is easy to chip, loses its sharpness very quickly or what?
In a bit more detail.
Back in the late nineties Alvin Johnson (custom knife maker - student of metallurgy) in comparisons of 1095 vs ATS-34 (Bos) noted that 1095 held an edge much longer. This wasn't just him talking about work he did (though it included that) people who used his knives reported it, often doing very detailed work (Mike Swaim) but also just being used by guys who didn't know anything about the steels and just did use the ones that didn't work as well (butchers, cowboys).
However even when harder, 1095 does not have the wear resistance of ATS-34 which is a very high wear stainless. Alvin argued from the ASTM standpoint that steels which were designed to have fine cutting edges were designed in a very particular way and it wasn't simply wear resistance it was the ability of the steel to keep a fine cutting edge due to the microstructure.
Skip ahead a decade or so and Roman Landes did a PhD thesis on the very subject and measured the ability of steels to stay stable (keep their shape) under micro-loads on the edge. He found that carbide volume directly reduced this stability and thus Roman will prefer to use steels like AEB-L, S1, and similar. He also has extreme geometries on his knives, how extreme, well this is a chopping knife :
"0.2-0,25mm and an angle of 20-25°total and it still breaks bones wo chips"
That is an edge of < 0.010"/12.5 dps on a chopping blade which cuts bones.
Now put that in comparison to the common thickness/angles being discussed usually here, and arguments that even things like cutting cardboard is abusive as it chips/damages edges.
In short, if you are looking to optimize cutting ability, durability, sharpness and edge retention at high sharpness you will end up with steels in the < 5% carbide volume (with ideal microstructure).
Now to be clear not everyone wants this and some people want (or are willing to tolerate) reduced cutting ability, durability, sharpness, ease of sharpening for edge retention at low sharpness in slicing cuts.
Like most things in steels and cutlery it is a balance of what you want and that is why there are always multiple steels. Even the people who make steels like AEB-L will make others. For example Sandvik makes :
-12C27M
Doesn't have the edge stability of 13C26 (AEB-L) but is much more corrosion resistant to the point it is dishwasher safe.
-19C27
Much more coarse carbide structure, designed to hold a low sharpness in slicing abrasive media