Amorphous Steel

pfdietz writes "Researchers at Oak Ridge have achieved a holy grail of materials science: they have figured out how to produce amorphous (glassy) steel. The material is reported to be twice as hard and have twice the tensile strength of the strongest ultra-high tensile strength steel alloy."

Comments

Somebody explain this to me?

[orthogonal]

From the linked article: Steel, an alloy of mostly iron atoms with varying amounts of carbon and other elements, is ordinarily a crystal, with an internal structure consisting of neat rows of atoms. If produced quickly from a liquid phase, however, a disordered solid can result.

Ok, somebody who understands materials science explain this to me, please: is the amorphous steel's hardness and strength greater because the non-amorphous, crystalline steel breaks easily along a row of atoms, as if along a perforation, while the amorphous steel, lacking such an orderly structure, lacks long runs of bonds along which breaks can be easily made?

Pictorially, is it like this?

Fe-Fe-Fe-Fe regular, non-amorphous steel
|..|..|..| <--- break along this line
Fe-Fe-Fe-Fe

Fe-..-Fe-.-Fe amorphous steel
|.\-Fe-Fe/.| <--- no natural breaking line
Fe-Fe-Fe..-Fe

Re:Somebody explain this to me?

[furry_marmot]

There was an article in Discover magazine just a couple of months ago about this very thing. Not sure if it's online, but you can definitely find it at your local library.

One thing worth noting: While the tensile strength is increased greatly, it is also glass-like in that if you hit it with a baseball bat, it explodes in lots of little shards. It has to do with the lack of a lattice structure keeping it together.

Another thing I thought was interesting: steel knives sort of shed molecules and become deformed at the knife-edge when you use them, requiring you to sharpen them. Glassy steel knives wouldn't do this. You could literally pour yourself a knife in a mold and have a never-dulling knife -- assuming you don't drop it. :-)

Re:Thank you very much!

[Kevin Burtch]

I used to work in a machine-shop, both in design and in purchasing (for several years).

Reynolds and many others consider 6061 and 6063 to be marine-grade.

They also consider 7075 to be aircraft grade... twice the shear and tensile strength of 6061, but also twice as expensive (cost/lb).

The T-rating ("-T6") is a hardening that it receives after forming, irrelevant to the alloy.

As far as what is spec-ed out, I agree... you should be able to use 6k series in an airplane, for example in a coffie-pot-holder.
Oddly enough, we made a run of those for an airline, and they spec-ed it had to be 7075-T6.
And people wonder why air-fare is so expensive... bozos are making the decisions.

The reverse is true too... we made a run of bicycle crank-axles that were spec-ed to be 7075-T9! Hardly an airplane, but those puppies sure were expensive!