8cr13mov vs s30v

BenchCo Spydermade

BenchCo Spydermade

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Feb 10, 2014
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OK, so obviously there should be no comparison. When I look at the Rockwell hardness.they are both rated 58-60. S30v performs way better and holds an edge way longer and costs way more. How can this be that they have such close Rockwell hardness? What other variables are at work if this is true?
 
The molecular structures are different, the malleability is different, and the element percentages are different.
 
I don't know a whole lot about the stuff, but the 8cr13mov is probably a lot more brittle at the same rockwell hardness as the s30v. S30v is probably more stain resistant. Ease of sharpening...????? ...I'm also not sure what allows a knife to hold an edge longer. I'm pretty sure that's where the main value comes into play with the S30V, but I have no idea WHY it holds an edge better. It probably has to do with grain structure and molecular compound. I've heard some guys get real deep into what elements do what in the knife edge. It all gets crazy and someone other than me would need to describe it.
 
Carbides. Carbide volume, type, size, and hardness. Carbon content.

Those will be the main things affecting wear resistance.
 
S30V is a powder forged while 8Cr13MoV is not. S30V contains more Molybdenum and Vanadium. Molybdenum increases hardenability, machinability, and strength. Vanadium forms very hard carbide, and it is also carbide grain growth restrictor.

Yes, Carbide grain size,structure and how uniformity of an alloy makes the difference within given hardness.
 
Depending on how you use your knives and how frequently you sharpen, they're not as far apart as you'd think.
 
For the past week I have been using a Kershaw/Emerson 4K and the 13Cr is holding up very well.
I am very impressed with it as it takes a razor sharp edge and no chips or rolls so far but I have only cut cardboard, rope, and netting so far.
When I get to cutting zip ties will be a good test.
 
BenchCo Spydermade said:
OK, so obviously there should be no comparison. When I look at the Rockwell hardness.they are both rated 58-60. S30v performs way better and holds an edge way longer and costs way more. How can this be that they have such close Rockwell hardness? What other variables are at work if this is true?
Click to expand...

Lots of steels are rated at being anywhere from 58-60Rc, from a lot of different companies. That is not a criteria for price. The reason there is a cost difference is because 8Cr is a Chinese alloy that does not cost much to buy, process, or heat treat according to manufacturers. S30V is an American made steel that does have a mor expensive heat treating protocol and not every company out there wants to grind and use it. That is the most basic variable around, Chinese steel vs American steel.
 
BenchCo Spydermade said:
OK, so obviously there should be no comparison.
Click to expand...



That statement is correct.

8cr13mov is a Chinese steel that was touted as being like 440C when first introduced.

According to Sal Glesser this steel is closer to AUS-8 (AUS8) than American 440C, and is often compared to AUS-8 and 440B.

Often considered to be a high end budget steel (an oxymoron if there ever was one).

Still, it's a very decent steel, offering a good balance between edge retention and ease of sharpening.


Now, CPM S30V is a different story.

One of Crucibles high end particle steels, it's carbine rich matrix offering a magnitude more abrasion resistance then a simple stainless like 8cr13mov.

Of course it's also much harder to grind/polish/sharpen, so it's not liked by some knifemakers and users.

When properly done it's an exceptional steel, but not everyone has the skills/patients to deal with it.

CPM S35VN is easier to work, and offers almost as much performance.


So, like you have stated, there should be no comparison.




Big Mike
 
thanks to all for your answers and contributions. there is much to be learned here.
Big Mike said:
That statement is correct.

8cr13mov is a Chinese steel that was touted as being like 440C when first introduced.

According to Sal Glesser this steel is closer to AUS-8 (AUS8) than American 440C, and is often compared to AUS-8 and 440B.

Often considered to be a high end budget steel (an oxymoron if there ever was one).

Still, it's a very decent steel, offering a good balance between edge retention and ease of sharpening.


Now, CPM S30V is a different story.

One of Crucibles high end particle steels, it's carbine rich matrix offering a magnitude more abrasion resistance then a simple stainless like 8cr13mov.

Of course it's also much harder to grind/polish/sharpen, so it's not liked by some knifemakers and users.

When properly done it's an exceptional steel, but not everyone has the skills/patients to deal with it.

CPM S35VN is easier to work, and offers almost as much performance.


So, like you have stated, there should be no comparison.




Big Mike
Click to expand...
thanks, this explains a lot. I have gotten annoyed at times sharpening my s30v as I can sometimes lack patience, but I like having a steel that will last for a while. I always assumed s35vn would be even harder to sharpen. I don't have any, but may have to try it out after reading your post.
 
BenchCo Spydermade said:
...this explains a lot. I have gotten annoyed at times sharpening my s30v as I can sometimes lack patience, but I like having a steel that will last for a while. I always assumed s35vn would be even harder to sharpen. I don't have any, but may have to try it out after reading your post.
Click to expand...


CPM S35VN was crucibles response to the complaints knifemakers where making about working S30V.

It grinds/polishes/sharpens more readily then S30V.

For many users the ease of sharpening out ways the slight loss in edge retention.



Big Mike
 
I believe I saw an interview with Chris Reeves of CRK. Chris said he partnered with Crucible to develop s30v for his blade steel. If I am not mistaken, this is a powder steel that is super heated then cryogenically quenched. It is supposed to to have very good edge retention with a very high corrosion resistance. Definitely an American steel.
 
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murfdog67 said:
I believe I saw an interview with Chris Reeves of CRK. Chris said he partnered with Crucible to develop s30v for his blade steel. If I am not mistaken, this is a powder steel that is super heated then cryogenically quenched. It is supposed to to have very good edge retention with a very high corrosion resistance. Definitely an American steel.
Click to expand...



Even CRK has switched to S35VN.

A move some folks lamented.




Big Mike
 
Big Mike you are far more knowledgeable about blade steels. I was simply adding what I knew and had seen in a Chris Reeves interview..To show you my novice mind. I really like VG10. Go figure. Thanks for the info
 
You can have most all of the cutlery steels we used heat treated from 55-62 on the Rockwell tester.

That is just a measurement that we use for a reference of hardness and has really nothing to do with how two different steels will preform. One is a c- grade used in china for cheap cutlery and the other is a excellent edge holding tough steel made here in the USA.
 
I like reading what you guys have to say about this stuff. But for my part, if a steel holds a decent edge for a good while and is not impossible to sharpen, its okay with me. Except for crap steel that you get on junk knives, they all seem pretty much the same to me. I do notice some excellent edge retention with D2, which never seems to loose an edge, but I just don't use my blades hard enough to tell the difference between 8Cr13MoV and S30V. If I were cutting boxes or shingles all day, the differences would probably become more apparent.
 
Im an "affordable knife connoiseur" (also known as a tight wad or cheap azz! :D:D) No surprise, ive got a TON of knives in both 8cr13/14 and Aus 8. This may just be me, but every single 8cr blade seems to have noticeably better edge retention than those of Aus 8. This is just my observation. I am fully aware that while composition is very similar, to me the 8cr chinese steels seem to be a better sum of their parts the japanese Aus 8. Anyone else have similar experiences as I with this?
 
Rhinoknives1 said:
You can have most all of the cutlery steels we used heat treated from 55-62 on the Rockwell tester.

That is just a measurement that we use for a reference of hardness and has really nothing to do with how two different steels will preform. One is a c- grade used in china for cheap cutlery and the other is a excellent edge holding tough steel made here in the USA.
Click to expand...

I learn much in these threads on knife steel. I will never be close to an expert but more of a dilettante.

The above statement says a lot. There is more than the hardness of a metal. There is also how "tough" it is. Toughness in this case being a finer, harder grain structure?

"Tough" was always a bit hard for me to wrap my head around.

Stainless is a pain to machine even though it is soft. They say it's tough". Toughness in this case meaning it's gummy and hard to rip apart, even though it bends and deforms easily.

Toughness in a carbon steel machete means the edge will roll before it breaks, it's not brittle.

There's abrasion resistance and other factors also I suppose.
 
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