Heat sinking (what kind of metal to use?)

[diachi]

[quote author=Diachi link=1218768567/0#8 date=1218793853]Diamond ;D

Don't look at me like that, its a better thermal conductor than silver

Yea I know, it's like 20 times better than aluminum , but a whole s%#t load more expensive.And unmachineable.Who would use diamond for heatsinking? :-/[/quote]

Just use common brown diamons, they are much cheaper than the ones you would find in jewelery, Infact you may find a lot of saws use diamond tipped blades

 

[Switch]

But I'm guessing they aren't pure.And I think they would still be imposible to machine. :-/

 

[diachi]

Well they aren't pure diamond, thats why they aren't white, but they are cheaper than white anyway, and I'm sure you could find a way to drill them.

 

[pullbangdead]

Drill a hole in a diamond? Really? You know it is the hardest substance known to man, right? And it being so hard makes it EXTREMELY brittle. Drilling a hole in it is a different story than just cutting/grinding/polishing it to make a gemstone out of it. What do you use to drill the hardest thing known to man?

And the less perfect a diamond is, the less the thermal conductivity will be. It is such a good thermal conductor because it is a nearly-perfect crystal with very few imperfections. When you're transmitting your heat through phonons (such as with a diamond), every imperfection is a scattering center, so every imperfection makes it worse. By the time it's not even transparent anymore (you say it's brown), it's likely that it's not nearly as thermally conductive anymore either, so not anywhere near worth it.

 

[artix]

What is wrong with a synthetic diamond?

 

[Murudai]

Drill a hole in a diamond? Really? You know it is the hardest substance known to man, right? And it being so hard makes it EXTREMELY brittle. Drilling a hole in it is a different story than just cutting/grinding/polishing it to make a gemstone out of it. What do you use to drill the hardest thing known to man?

Uh, they use steel drill bits to drill through steel.

So, what do you think they use on diamond http://en.wikipedia.org/wiki/Diamond_tool

 

[el-taco]

Fact I learnt: To successfully get through a substance, you need a substance in greater density to cut/drill with.

 

[VillageIdiot]

Density is just weight to size. You can cut lead with steel.

 

[Murudai]

Fact I learnt: To successfully get through a substance, you need a substance in greater density to cut/drill with.

Density has nothing to do with it. Aluminium is tough stuff, but it is very light. Lead is MANY times more dense than aluminium, but you could almost tear a sheet of lead with your bare hands. I've held sheets of lead before and heavy as it is, you can fold it and bend it as easy as cardboard.

Hardness isn't about how heavy and compacted the molecules in a material are, but how well they bind to each other.

 

[Midknight]

LoL, damn guys I'm not trying to make a pimp'n $100,000 laser.

LoL. Anyway. What if I use aluminum as the chunk. And just use a little bit of copper to house the laser diode.

This way I can sink the heat faster. And still have the aluminum to sink the copper... Make any sense?

 

[moond0ggie]

Seems like a good idea!
Like a LD in a module, inside a copper tube/pipe, inside an aluminum tube/pipe, stuffed in a host.

 

[brtaman]

Hey,

Unless you get a perfect "fit" between the metals you would be better off to just use a piece of either copper or alu. But you could get the copper into the alu by heating the alu up and by cooling the copper down, and then press fit it together and let the metals expand and contranct and viola you have a cooler. But I don't think it would be worth your trouble, these diodes put out like 1W of energy max...



brtaman