How is this manufactured? I'm stumped 1

[themilkmaid]

I'm working on a project that requires a heat sink for a high power LED. The unit shown in the linked images works well, the problem is that I can't figure out how it was manufactured and I need to create something similar but customized to this project.

This heat sink is from a fairly high volume product. The material is aluminum, and it's anodized. The part is not machined, there are very sharp inside corners that they would never bother with since they serve no purpose. There is 0deg draft on any of it, so it's not die cast. As far as I know you can't metal injection mold aluminum, so that's ruled out. There's no way a high volume part would be sand cast.

Am I missing something? Is there some sort of automated high volume equivalent to sand casting? The bottom face is smoothed with a secondary operation, but the rest of it can be a bit rough. I have Googled everything I can think of with no success.

Any ideas?

http://files.engineering.com/getfil...35-afe4-ffc3f8cd312f&file=20140422_233448.jpg

http://files.engineering.com/getfil...ea-a0da-f0993342be3e&file=20140422_233501.jpg

http://files.engineering.com/getfil...9b-a98f-bdea5d4f3c70&file=20140422_233526.jpg

 

[Medeski]

Really? Wow, I didn't realize that. The last time I had any contact with Radian was three jobs ago, so almost 12 years now. It was a custom heatsink project and all the engineering support and purchasing was done through Radian's California office, but I do seem to recall the actual fabrication being done overseas. I wonder if they were a reseller of Malico back then too.

 

[ScottyUK]

Another possibility:

http://www.aavid.com/product-group/bonded-fin;

there's a FAQ section on the page too.

 

[tbuelna]

I took a look at the websites for the companies that forge these heat sinks from aluminum or copper. The aspect ratios for the pins and fins they can achieve are quite impressive. I'd also like to know how they produce these forgings without draft and with sharp corners.

I'm familiar with the squeeze casting process used to produce larger aluminum components, like wheels, using higher strength alloys that cannot be made using conventional casting processes. The "forging" process used here seems like it might be similar. The aluminum preform is heated to a plastic condition (just below its melting point), and then it is rammed into a steel mold under high pressure. The primary limitation appears to be the total mass of the material being forged. It seems to be limited to parts weighing just a few ounces.