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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.
The old material was stiffer, not harder, than diamond. It could still be scratched by diamond.
Sweet.
A regular furnace and a zap of current is enough to meld boron with the metal rhenium....Sound familiar?
If this sounds familiar you need to get out more. Seriously.
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
When keying someone's car isn't enough to say I hate you, make a key out of this material and key their jewelery.
GAAH! MY PRINTER IS ON FIRE!!! PUT IT OUT! PUT IT OUT!
Again, we mustn't conflate hardness, stiffness, and toughness!
I've been studying diamond for a while now, and have a fairly prominent webpage about diamond's material properties, and on three separate occasions I have been contacted in the following way:
A budding fantasy author is writing a book in which the protagonist has a sword made out of diamond, "because diamond is the hardest material of all!", and they wanted to run the idea past me first.
So I point out that, despite being very hard (i.e. resistant to indentation), diamond is in fact very brittle (i.e. not very tough), and indeed the very first time that our hero hits something with his diamond sword, it will shatter.
In one case, the author said that I had basically ruined his life by wrecking the whole concept of the book that he had been writing for the last few years. In subsequent emails, he was begging me to come up with a solution (e.g. diamond sword, coated with steel, etc.?)...
Chuck Norris's toe nail clippings?
You laugh, but as a female geek I would be Seriously Impressed by a marriage proposal which featured a ring made from something exotic like that. Assuming that I was sufficiently insane to consent to marriage, I would forever after wear that ring and smirk at the Normals with their plain old diamonds.
FATMOUSE + YOU = FATMOUSE
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']
a mond_powder_price_list.html 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.
a sp 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.
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/di
http://www.metalprices.com/FreeSite/metals/re/re.
The not-so-trustworthy-looking http://biotsavart.tripod.com/bmt.htm has boron at about $5000 per kilogram, so $2200 per pound; still these are orders of magnitude cheaper than diamond.