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ArcticMyst Security by Avery

Why does aixiz make thier modules out of brass?

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Isn't brass, as far as most metals go, a poor condutor of heat?
I understand why they don;t use copper (difficulty machining it) but why not aluminum?
Aluminum machines easily and I believe is cheaper than brass.

Conductivity (W/mK):
Silver - 429
Copper - 401
Aluminum -250
Brass - 109

Aluminum has over 2X the conductivity of brass.
 
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Grix

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Brass is a very decent heat conductor, not very far behind aluminium. Plus thin aluminium would be brittle.
 
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Asherz

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Also cheaper isn't it? Considering the amount they make as well costs could get pretty high quickly, so while price difference may be little per module, when they order 100,000 batches it's probably a big saving.
 
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the lens module doesnt need to be too thermaly conductive. brass has many favorable qualities, corrosion resistance, strengths, machinability. etc.


michael.
 
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the lens module doesnt need to be too thermaly conductive. brass has many favorable qualities, corrosion resistance, strengths, machinability. etc.


michael.

I understand that, but the module also holds the diode, doesn't it ?
 
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these are not meant to be heat sinks, they are merely diode pockets. You should use another heat sink on top of the aixiz module.

Aluminum at those thicknesses would probably not work so great for press fitting. Aluminum is softer than brass, so pressing it might deform it instead of just pressing in like it should. If the module was a little thicker it probably would be made of aluminum.
 
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Thanks for explaining. Either way, I still think the module should conduct heat to the heatsink.
 
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Aluminum also has a higher coefficient of thermal expansion than brass, this smaller coefficient is needed to mach the diodes and hold them in place with a snug press fit.
 
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I guess I shouldn't have said harder, but stiffer. Pure aluminum is softer than brass, but most aluminum alloys are a little harder than brass. But aluminum alloys are more brittle and malleable than brass, I guess that could be considered softer :thinking:

Source? Personal experience. You can tell by the chips aluminum throws off compared to brass and the feedrates/cutting depths you can use on both. Aluminum is easier to work with than brass, thus harder.
 
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The only thing I don't care for is the chrome plating used. It acts like a blanket reducing heat transfer. Would be nice if the just kept them uncoated brass. They would loose some of their nice looks but would work better.
 
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well the looks arent really important. we mount them into hosts anyways.



michael
 
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I scuff them down and use solder and sandpaper to fit them perfectly in most all of my builds
 

Benm

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Brass or messing are actually pretty good material choices. Mechanically, they are superior to pure copper since that would probably be too malleable for a good press fit and long lasting threads.

Aluminium could be usable too, but that has its difficulties as well - it forms an oxide layer that can interfere with electrical (and to some degree thermal) contact performance. Also, brass can be soldered if need be, although i don't think thats a consideration for these modules (?).
 




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