# How hard is too hard?? HRC 70+ Amorphous Alloy.



## DitmasPork (Jul 13, 2017)

Firstly, most of my J-knives are in the 5962 HRC range.

I noticed the "Liquidiamond Chef's*Knife" on the Food52 site. On the blade it says "Amorphous Alloy" and "HRC 70+."

What is "Amorphous Alloy"?

What are the advantages and drawbacks to having the steel at HRC 70+?


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## pete84 (Jul 13, 2017)

Amorphous? Metal that constantly changes shape? Doesn't seem like a very stable option :lol2:

It must be the T1000 of knives.


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## DanHumphrey (Jul 13, 2017)

I... yeah. That makes no sense. And hardness is not the only important characteristic of steel for knife-making, and arguably is too focused-on to the exclusion of other factors.


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## cheflivengood (Jul 13, 2017)

it would be nearly impossible to sharpen on stones


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## DitmasPork (Jul 13, 2017)

DanHumphrey said:


> I... yeah. That makes no sense. And hardness is not the only important characteristic of steel for knife-making, and arguably is too focused-on to the exclusion of other factors.



Yup, I know that steel hardness is only one aspect of what makes a good knife. 

The description seemed weird:
"...The Liquidiamond Chefs Knife comes out of the box razor sharp but, unlike even high-quality steel or ceramic knives, it requires minimal sharpening (after years of use) to maintain its edge. A patented metal alloy, developed through collaboration with NASA, forms the stainless steel blades cutting edge, leaving it cutting like new, even after heavy use. Sounds too good to be true?..."


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## DanHumphrey (Jul 13, 2017)

Too good to be true. By far. "Collaboration with NASA" is a term bandied about by snake oil salesmen all the time, because it sounds amazing (and there is amazing stuff that comes from them). Also though, things like baby formula, the thermometers that go in your ear, and the DustBuster. "Collaboration with NASA" does not mean that it's cutting-edge, futuristic, or amazing. Most of it is stuff that you take for granted in daily life.


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## fatboylim (Jul 13, 2017)

DanHumphrey said:


> "Collaboration with NASA" does not mean that it's cutting-edge, futuristic, or amazing. Most of it is stuff that you take for granted in daily life.



+1 

We would have personal computers if it weren't for defence/NASA developments; they are not bragging about it!


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## LifeByA1000Cuts (Jul 13, 2017)

An "amorphous alloy" would be one that isn't crystalline. A metallic glass.


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## chinacats (Jul 13, 2017)

I believe the sweet spot to me is 62-65...as others have said though,there are other more important factors.


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## StonedEdge (Jul 13, 2017)

DitmasPork said:


> Firstly, most of my J-knives are in the 5962 HRC range.
> 
> I noticed the "Liquidiamond Chef's*Knife" on the Food52 site. On the blade it says "Amorphous Alloy" and "HRC 70+."
> 
> ...



I think they made a movie about this knife, it was called Terminator 2.


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## JBroida (Jul 13, 2017)

I've had a chance to use and sharpen a few different versions of these and so far nothing has been impressive in any way... also, there's no way they are that hard... I was able to sharpen with regular stones... even the king 1000/6000 was fine.


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## ecrphoto (Jul 13, 2017)

+1 I owned a Vmatter knife (which is the precursor to this new branded launch), brought it to Jon to sharpen, and have sharpened it myself a few times. But not many times, because the thing doesn't hold an edge, and wasn't worth the time. Perhaps the new models are different, but now that Santoku is in my camping kit because I don't feel bad using it to chop on a tree stump if I'm out car camping....


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## DitmasPork (Jul 14, 2017)

JBroida said:


> I've had a chance to use and sharpen a few different versions of these and so far nothing has been impressive in any way... also, there's no way they are that hard... I was able to sharpen with regular stones... even the king 1000/6000 was fine.









Jon. Question for youwhat is the device used to gauge HRC, aren't they all calibrated the same? 

I know that HRC is only one aspect of knife makingi.e. F&F, grind, profile, handle design, etc.my impression is that a harder steel makes for a longer lasting edge, but can also be more brittle and less durable, and super hard steel won't get as sharp as good carbon. Please correct me if I'm wrong.

Out of curiosity, I had gone to the Liquid Diamond website, does seem like a lot of hyperbolic marketing-speak. Here's from the site:

======
LIQUIDIAMOND was born of the most significant material technology breakthrough since the discovery of thermoplastics; Amorphous Metal. Working with Caltech and NASA scientists, our founders brought forth this next generation material and applied it to real world solutions. After decades of research & development and commercialization in industrial and highly engineered products, we identified the knife market as an ideal application for this technology.

Having reached the practical limitations of the existing materials (steel and ceramics), LIQUIDIAMOND Knives endeavored to deliver superior performance and value to this centuries old product. With the unique physical properties of Amorphous Metal and our advanced manufacturing technology, we found a way to do just that. *A knife as sharp as the highest quality steel or ceramic knives yet far more durable than any; able to hold an edge many times longer than any knife out there today.* And better yet, because of our material, approach, and manufacturing technology, we are able to deliver this superior product at a price that is affordable for the largest possible number of consumers. {I've bolded text worth noting}
======

So, an inexpensive knife that's sharper, longer lasting edge, more durable, than any knife out there is pure marketing.


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## CoteRotie (Feb 27, 2019)

Amorphous metal has some really useful properties in electronics. I think Bendix commercialized it first for transformers- They shot a jet of molten metal at the edge of a high-speed spinning wheel which caused it to cool into thin ribbons so quickly it couldn't form a crystalline structure (grains), so it was amorphous, literally a metal glass. They took the ribbons and wound them into toroids for transformers. Later others powdered and sintered the amorphous metal with binders to make other transformer core shapes.

I have no idea how they would get billets or slabs of amorphous steel for a knife, I'd love to find out. I'd assume that heating the steel to forging temperatures might ruin the amorphous structure, so maybe they're stamped or machined??

I'd like to hear Larrin's take on this.


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## inferno (Feb 27, 2019)

I'm guessing its liquidmetal kinda like lm2 (I think).
https://en.wikipedia.org/wiki/Liquidmetal

there have been knives made with this many years ago. I read it on BF. probably too expensive though.
search for liquidmetal on bladeforums.


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## ACHiPo (Feb 28, 2019)

Here's my shot at decoding the marketing jargon: 
liquid--amorphous (as others have said)
diamond--carbon

My guess is that they took mediocre, cheap stainless steel, stamped it, put a decent edge on it, then coated with amorphous carbon in a chemical vapor deposition system. Amorphous carbon can have some pretty cool properties, including being very hard (and brittle). Put on a ductile substrate, you might have a decent composite material that would hold an edge for quite a while if not damaged (or sharpened). It would be very wear resistant, but not hold up well if contacting hard stuff (bone, ceramic).

Of course the name could mean nothing at all and be total hookum.

Think I'll pass.


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## bahamaroot (Feb 28, 2019)

ACHiPo said:


> *Here's my shot at decoding the marketing jargon: *
> liquid--amorphous (as others have said)
> diamond--carbon
> 
> ...


*Here's my shot at decoding the marketing jargon:
*
Liquid Diamond, Amorphous Metal developed with Caltech and NASA scientists = We describe it with a bunch of cool sounding terms to hide the fact that it is a crap knife.


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## ACHiPo (Feb 28, 2019)

bahamaroot said:


> *Here's my shot at decoding the marketing jargon:
> *
> Liquid Diamond, Amorphous Metal developed with Caltech and NASA scientists = We describe it with a bunch of cool sounding terms to hide the fact that it is a crap knife.


Well that's a definite possibility!


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## GorillaGrunt (Mar 1, 2019)

Sounded like some sort of coating to me. The guy I used to work with who was a sucker for this junk had one too, all I remember is that it wasn’t well ground, didn’t actually hold an edge, and about 1cm of the tip snapped off pretty quickly (although to be fair, someone probably did something stupid with it).


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## CoteRotie (Mar 1, 2019)

GorillaGrunt said:


> Sounded like some sort of coating to me. The guy I used to work with who was a sucker for this junk had one too, all I remember is that it wasn’t well ground, didn’t actually hold an edge, and about 1cm of the tip snapped off pretty quickly (although to be fair, someone probably did something stupid with it).


Yeah, they make reference to an amorphous metal alloy bonded to the edge somehow. So could be a coating of some sort, but clearly the knife is not made of amorphous metal. Sounds almost as hokey as the guy with the diamonds and UV light built into the blade. Amorphous alloy might be a good edge material, if you could figure out a way to use it, but I don't think this implementation is anything other than marketing hype.


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## Barmoley (Mar 1, 2019)

Amorphous metal alloy is not steel and in theory is not a bad idea. Can you imagine casting and molding an almost fully shaped blade, with grind and profile already done. Or 3D print blades of any shape and only having to do final sharpening, if that. Some of these alloys are very wear resistant, can get very hard and have very high corrosion resistance. I think the issue in knife applications has been similar to ceramics, these alloys being very brittle. Glass like structure seems to have its negatives. If with more development they can overcome this somehow, we might just see new alloys as material of choice in the future of knives. At the moment though, steel rules.


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## Nikabrik (Mar 1, 2019)

I also would have assumed that it was a coating - in particular, perhaps some sort of amorphous physical vapor deposition such as DLC. However, this video makes me think there's actually a wee strip welded along the edge: 

It turns out Fe-based bulk metallic glasses can be quite hard - in this study, about 67 HRC: 
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.462.5344&rep=rep1&type=pdf

However, there are some differences that could make the BMG different from what we normally expect:
First, poor ductility is common - which could make burr formation nonexistent.
Secondly, the material apparently seems to spall about 43° from the direction of force when machined or overstressed. I wonder if that would prevent the very edge from ever being at a fine angle.


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## CoteRotie (Mar 1, 2019)

Barmoley said:


> Amorphous metal alloy is not steel .



Absolutely correct, I should have said "amorphous alloy" not "amorphous steel". Actually amorphous metal alloys can have significant toughness and flexibility. The one I am familiar with from my work is Metglas: https://en.wikipedia.org/wiki/Metglas


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## inferno (Mar 1, 2019)

this is the first use of liquidmetal for knives

https://bladeforums.com/threads/liquid-metal-is-here-well-at-least-some-prototypes.236043


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## CoteRotie (Mar 1, 2019)

Very interesting- I didn't know that they found a way to make amorphous alloys that can cool relatively slowly and stay amorphous.


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## gman (Mar 1, 2019)

sounds like pure woo


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