Easy-to-Make Material Scratches Diamond

holy_calamity writes "A material tough enough to scratch diamond that can be made without resorting to massive pressure has been developed at UCLA. A regular furnace and a zap of current is enough to meld boron with the metal rhenium." Sound familiar? This is the other new material tougher than diamond, but no word yet on how they rate against each other.

Stiffer, not harder

[caramelcarrot]

The old material was stiffer, not harder, than diamond. It could still be scratched by diamond.

Re:Obligatory...

[Anonymous Coward]

Wrong. The use of hollow point and similar ammo during times of war is restricted by the Hague convention of 1899, not the Geneva convention. Also note that tumbling and frangible full metal jacket ammo is allowed, such as British mark 7 .303

Re:Obligatory...

[Daniel Dvorkin]

Military ammo usually lacks quality (b) because it's better to disable an enemy soldier than to kill him, both for the psychological effect at the enemy, who has to watch him suffer; and because his buddies will be busy rescuing him instead of fighting. Oh, and because the Geneva convention says so, they seem to think it's somehow more "humane" to cripple soldiers than to kill them.

God, I wish this dumb myth would die.

First: there is no infantry weapons system (other than the "NLW" which are designed for crowd control, not combat) specifically intended to cripple rather than kill an enemy. One shot, one kill, is always the infantryman's goal. The best possible way to remove an enemy soldier from the fight is to kill him; wounded enemies often can and do keep shooting back. The "wounding is better than killing" meme is often repeated among soldiers as well as civilians, but it does not appear anywhere in Army doctrine.

Second: the LOAC's prohibition on "dum-dum" rounds is basically intended to make things easier on military surgeons; it's a matter of what's humane off the battlefield, not on it.

Third: FMJ rounds, as opposed to the wide variety of other types of rounds which would be acceptable under the LOAC, are used primarily for reliability and versatility. Reliability, because rounds with any exposed lead will foul a rifle under typical infantry combat conditions (dirt, mud, sand, and enormous volume of fire between cleanings.) Versatility, because softer rounds are better for use against unarmored human targets, but that's about it. Trying to stop a vehicle with soft-nose rounds? Good luck. And modern body armor is very very good, but you've still got a good chance of getting through it with a dead-on shot from a rifle of decent caliber if you're using FMJ; soft-nose will just go splat.

Re:Hardness, stiffness, and toughness

[Kjella]

Something tells me the author won't be very successful if he can't write himself out of that corner. Even if it was possible, would you in a fantasy novel explain it's a diamond-steel alloy with micrograin and internal stress? Any of the following should work:

a) The sword is magical. If it's that central, it should be anyway and so it's the magic making it indestructable, not the material
b) The sword isn't actually of diamond, but the material is unknown and looks like it, so it's been given a poetic name
c) It's been created in a magical forge or forger, and doesn't have the properties of diamond (sorta a) but less emphasis on the sword's power)
d) In the hands of the wielder, it changes power (something along the lines of the power flowing through it)
e) Don't actually explain why, it's fantasy after all

Certainly a) and b) should be trivial to implement. After all, I assume he must have taken more than a few liberties with reality already to explain how a diamond sword came into being.

Re:IMPOSSIBLE!

[kippers]

Diamond ain't metal. It is made of Carbon.

Re:IMPOSSIBLE!

[Anonymous Coward]

Violation of rules 1 and 2.

Anonymous does not forgive.

Re:IMPOSSIBLE!

[Anonymous Coward]

gb2gaia

Re:Hardness, stiffness, and toughness

[Anonymous Coward]

Katana are forged from steel, not different metals. How the steel is quenched gives it a different properties. Pearlite (soft, flexible) and martensite (hard, brittle) are steel which is cooled at different rates, and to use these properties, katana are painted with layers of clay before quenching. The curve happens because of the different cooling rates of the steel because of the clay.

Re:IMPOSSIBLE!

[Anonymous Coward]

Thank god for fourchon.

This costs about 5x abrasive-grade diamond

[Tom Womack]

Rhenium costs £6.50 per gram if you want to buy it on ebay; boron is £13.50 a gram on ebay because the one seller there is selling an exotic crystalline form. [ebay search for 'rhenium metal' or 'boron element']

So making ReB2 using source materials bought in small quantities on ebay would be about ten pounds (about twenty dollars) a gram; probably the cost of the electricity to run the furnace would be more than that, and the depreciation on the furnace more still.

I paid ten Euros (about fifteen dollars) for the diamond sample I have, which is two milligrams, and various diamond-industry sites give prices on the order of a hundred thousand dollars per gram; of course, rather like microchips, diamond pricing is exponential in the size because you have to find one big diamond rather than gluing two small ones together.

But ReB2 will be competing with diamond abrasive, and http://www.diamondtech.com/products/categories/dia mond_powder_price_list.html [diamondtech.com] will sell you twenty grams (a hundred carats) of half-micron diamond dust for fifty dollars which is a lot cheaper than either the rhenium or the boron.

http://www.metalprices.com/FreeSite/metals/re/re.a sp [metalprices.com] suggests that bulk rhenium is $3000 per pound, which is a bit over half the ebay price above; some sites, I think mostly run by gold bugs, suggest $6000 per troy ounce, so either there's an opportunity for arbitrage, or they've confused rhenium and rhodium.

The not-so-trustworthy-looking http://biotsavart.tripod.com/bmt.htm [tripod.com] has boron at about $5000 per kilogram, so $2200 per pound; still these are orders of magnitude cheaper than diamond.

Re:IMPOSSIBLE!

[Anonymous Coward]

http://uncyclopedia.org/wiki/Diamond [uncyclopedia.org] - found here

Re:Obligatory...

[Daniel Dvorkin]

As another reply to your post pointed out, the reason to "shoot for the belly" is not to wound (vs. kill) the target, it's because by aiming for the "center of mass" you have the best chance of actually hitting your target. Snipers can go for the fancy head shots; regular grunts in the middle of a firefight don't have the time. And gut wounds are very often fatal.

Only in movies, soldiers continue shooting like madmen after being shot in the belly.

I have personally seen people with horrific wounds continue to fight.

I have also a medical corps man training and I know that the enemy will try to strain the medical logistics and other support units in a conflict.

Any combat will strain medical logistics, with or without a deliberate "shoot to wound" policy. Overall, "shoot to wound" would probably create less strain on logistics because if you're not trying to shoot to kill, you're much less likely not to hit your target at all. Any army which tried not to kill its opponents would find it itself at an enormous disadvantage on the battlefield against any army which tried (as in fact all armies do) to kill as many as possible; what the medics are doing is irrelavant if the infantrymen fail to accomplish their mission. And I speak as someone who's done both jobs -- I liked being a medic a lot more than I liked being a grunt, but the simple fact is that medics don't win wars.