# Steel.



## Cryozombie (Sep 25, 2008)

Hey, just a question...

is AUS 6 decent knife steel or not?  I see a lot of folk online saying "Go with 440 Stainless instead" but I'm curious is thats a realistic opinion?

I don't know much about AUS 6 at all, except a blurb I read on like "Wikianswers" when I googled it that said it was a decent japanese knife steel... whatever that means.


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## Flying Crane (Sep 25, 2008)

Correct me if I'm wrong, but doesn't the "440" refer to the hardness to which it is hardened and tempered?  I believe there are a number of different types of "stainless" steel.  But I don't think "440 Stainless Steel" itself is something specific, only a somewhat generic description.


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## arnisador (Sep 25, 2008)

Limited info. here.


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## cdunn (Sep 25, 2008)

Flying Crane said:


> Correct me if I'm wrong, but doesn't the "440" refer to the hardness to which it is hardened and tempered? I believe there are a number of different types of "stainless" steel. But I don't think "440 Stainless Steel" itself is something specific, only a somewhat generic description.


 
All AISI grades, such as "440 Stainless refer" to a specfic range of compositions. While there are many 'stainless' steels, each of them generally refers to a different composition, rather than a specific processing. 

440 stainless, specifically, is a steel consisting of 16-18% Cr, 0.75% Mo, 1.0% Mn, a carbon content of 0.65 to 1.2% depending on specific grade (A,B,C), and balance Fe. Commonly, it can be annealed for a toughness comparable to a mid-carbon steel, or alternatively, it can be quenched and tempered to be extremely hard, but very brittle. 

AUS-6 has much less chromium and a bit less carbon, and a kiss of nickel - I'm not 100% certain of the effects of nickel in steel, so these are informed guesswork, but, in comparison to 440 stainless, it will not hold an edge quite as well, but in return, it will be more difficult to break the blade.

From that, you want to match your material to your applications. If your knife is short, and you plan on mostly making well controlled cuts with little chance of blade twisting or leverage, then the 440 is your preferred choice. If you've got a slightly longer knife, or you expect a higher need to survive being twisted or bent, then the AUS-6 knife may have a longer lifetime.

The extreme case of this, of course, is the sword, where the lateral and torsional abuse rate is extreme, and stainless steels generally become lackluster at best or hazardous to the user at worst, due to the high chromium content reducing the ductility and flexibility of the blade.


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## KenpoTex (Sep 26, 2008)

AUS 6 is fine...really, as long as the knife is made by a reputable manufacturer, I don't think it really matters all that much.

Yes, some steels are better than others for certain things, but (not aiming this at anyone in particular) IMO most people really don't use a knife often enough for it to matter.  Most people also don't know how to sharpen a knife very well so again, it doesn't really matter.


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## cdunn (Sep 26, 2008)

KenpoTex said:


> Yes, some steels are better than others for certain things, but (not aiming this at anyone in particular) IMO most people really don't use a knife often enough for it to matter.  Most people also don't know how to sharpen a knife very well so again, it doesn't really matter.



Probably true. But design overkill is fun. verkill:


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## Cryozombie (Sep 27, 2008)

KenpoTex said:


> AUS 6 is fine...really, as long as the knife is made by a reputable manufacturer, I don't think it really matters all that much.


 
Actually, I was looking at some "Assemble your own knife kits" just for a kinda fun weekend sorta project, and one of the ones I liked, listed the steel as AUS 6 and I was unsure if it was decent knife steel.  It's not like I expect my finished product to be a superior knife, but I at least want it to be good enough I can say "Look, I built this!" to people.


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## KenpoTex (Sep 27, 2008)

I see...I've got one or two that are AUS 6 and they've held up just fine.


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## Ramirez (Nov 22, 2008)

There is a good review of steels here.

http://www.cutleryscience.com/reviews/blade_materials.html


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## shesulsa (Nov 22, 2008)

Ramirez said:


> There is a good review of steels here.
> 
> http://www.cutleryscience.com/reviews/blade_materials.html



Thanks!


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## BlueDragon1981 (Nov 24, 2008)

I work for a machining company that links me indirectly with steel. Not that kind of steel however. We machine low carbon steel. None of it nearly as small as a knife or sword for that matter. 

Metallurgy and steel is interesting though. A lot more goes behind it than one might think. Chemistry and math is defiantly part of it.


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## David43515 (Apr 10, 2009)

I spent seven years working as a knifemaker in the custom shop at Busse Combat Knife Co.  For the most part the 440 series of steels (440a,440b, and 440c) is used in factory-made knives for two reasons. 1) It`s easy to work with so the grinding belts need to be changed less often. 2) It doesn`t rust easily.

But the high chromium content that keeps it from rusting also makes it brittle so the sharp edge dulls quickly. It`s actually chipping on the microscopic level. We used to say that unless you`re looking for a scuba knife and your #1 concern is rust, the only thing 440 is good for is door stops.

I`ve never worked with AUS 6, but I`ve heard it`s being used by people whose opinions I respect.


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## Carol (Apr 10, 2009)

The 440 grades are fine for swords but I don't particularly like them in knives.

AUS-6 is a grade that has lower carbon content, like 440.   Its not going to hold an edge as well as the steel with higher carbon content (AUS-8, VG-10), but it does make for a tough blade that is resistant to rust.

Can't say I've used AUS-6 or any of the lower carbon grades. I use the higher carbon grades in my own blades.


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## Bikewr (Apr 11, 2009)

Just my opinion, but I think sometimes folks get a bit hung up on the "best" steels for knives intended as weapons.

Lets face it, we are not going to be whittling hardwood logs into toothpicks or skinning bears.    As long as a knife is well-constructed and is capable of taking a good edge, chances are it has to stay sharp only the one time....

Knives of choice for "street" people are generally cast-off or stolen kitchen items or pocketed steak-house knives.   I don't think I've ever encountered a "tactical" knife on a suspect.


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## Carol (Apr 11, 2009)

Bikewr said:


> Just my opinion, but I think sometimes folks get a bit hung up on the "best" steels for knives intended as weapons.



That could be.  If one is only concerned about sticking the pointy end in a BG that one time then it likely doesn't much matter.

Personally though...I've never used a knife as a weapon.  I do use it, however, for many other things...so my opinion is based on what I have used it for, and not what I haven't used it for. :asian:


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## arnisador (Apr 11, 2009)

I dunno...I'm glad someone knowledgeable is worrying about it for me! I may be relying on that weapon some day.


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## lklawson (Apr 13, 2009)

Carol Kaur said:


> The 440 grades are fine for swords


I have to disagree.  440 is fine for swords intended for decoration or pageantry but then any steel would work fine for that.

For swords that you intend to cut, thrust, or parry with, 440 is simply not appropriate.

Peace favor your sword,
Kirk


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## lklawson (Apr 13, 2009)

An oldie but a goodie:

Steel grades: http://www.angelic.org/highlander/metallurgy/grades.html

Peace favor your sword,
Kirk


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