What makes diamond so excellent for drilling?

[PippaBG]

I know about the strong covelant bonds, but just why is diamond so much better than any other material for drilling?

 

[Rajini]

It is difficult to say precisely!
As far as i know the main property of diamond is hardness, which makes it essential for the using in drilling tools.

 

[xxChrisxx]

Very hard material, meaning you can drill other hard materials. Only the high wear surfeces are coated in it.

Hard material + soft drillbit = ruined drillbit

 

[Andy Resnick]

I know about the strong covelant bonds, but just why is diamond so much better than any other material for drilling?

That's a good question- material properties like 'hardness', 'toughness', and 'strength' are difficult to predict. Diamond appears to be very hard but very brittle- see for example

www.lbl.gov/ritchie/Library/PDF/Drory_diamond_APL.pdf

and

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TWV-44S5BHG-38&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1155472086&_rerunOrigin=google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=883d11657f603b8918ef6c890ddbe287


I suspect this relates to the rate a diamond bit must be replaced. I'm not sure it is 'better than any other material'.

 

[diazona]

Let's see... for drilling, you're basically trying to get the drill bit to scratch away the material you're drilling into, and not the other way around. Diamond is better at scratching (and harder to scratch away itself) than any other natural material. But as for the microscopic-level physical explanation of that property? I'd imagine it has a lot to do with the tetrahedral lattice, which is generally a very strong structure... but I couldn't say much in detail.