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Adiabatics
04-14-2010, 09:29 AM
I seek guidance on the best procedure to stir cast silicon carbide into 1100 aluminum.

What is the best fluxing agent?

What should be the ratio of fluxing agent to aluminum by weight?

What is the most cost efficient method to minimize oxidation?

Is there a good web site that helps explain the process?

Evan
04-14-2010, 09:32 AM
I haven't clue what you are talking about. Care to explain?

Dr Stan
04-14-2010, 10:45 AM
Sounds like he's trying to create an alloy. However, the melting point is 2730 C, well above the ignition point for aluminum.

He could also be attempting to create a suspension, but I'm not too sure how that would work.

dvbydt
04-14-2010, 11:17 AM
My guess is a suspension (MMC). They are roughly the same density. Used as lightweight brake rotors for racing I believe but I do not know any details. Don't think it was successful.

IanR

Evan
04-14-2010, 11:25 AM
Brake rotors? 1100 aluminum is dead soft unalloyed electrical aluminum.

bob_s
04-14-2010, 11:45 AM
see chapter 10 of

Multicomponent Phase Diagrams: Applications for Commercial Aluminum Alloys

Edited by Dmitry G. Eskin, Nikolay A. Belov and Andrei A Aksenov

424 pages
Trim Size 6 1/2 X 9 7/16 in
Copyright 2005
USD 265.00, Hardcover, Reference

Ernie
04-14-2010, 12:27 PM
Sounds to me like he wants to stir in some abrasive into molten aluminum so when it silidifies, he has an abrasive pad made of solid aluminum???
Ernie

bborr01
04-14-2010, 12:41 PM
Sounds to me like he wants to stir in some abrasive into molten aluminum so when it silidifies, he has an abrasive pad made of solid aluminum???
Ernie

That is what I am thinking too. We need a little more informtion.

Brian

ckelloug
04-14-2010, 01:30 PM
He is making a metal matrix particle composite. I don't know the solubility of silicon carbide in Aluminum but as long as it is not soluble, it should work provided he can get it dispersed adequately. Such a composite will possess a higher stiffness than aluminum although it is likely that the fill percentage would have to be quite high. This is essentially an aluminum version of epoxy granite. This composite will also have better wear resistance than aluminum. The largest problem will be adequately dispersing the particle phase as standard techniques don't work so well in molten metal.

See http://composites-by-design.com/?page_id=25
--Cameron

bborr01
04-14-2010, 01:34 PM
Seems to me like the two materials would want so separate out by specific gravity unless they could be somehow stirred until they were nearly ready to solidify.

Brian

Evan
04-14-2010, 01:50 PM
I''ll wait for our first time poster to explain instead of hazarding a wild guess as to his intent. As for possible applications for a composite of hard particles in a soft matrix, that is the recipe for babbit bearing materials.

ADGO_Racing
04-14-2010, 04:53 PM
Brake rotors? 1100 aluminum is dead soft unalloyed electrical aluminum.


Yes, Sprint cars use aluminum rotors. They hold up just fine on a car that weighs abut 1300 pounds and has about 800 HP. Yes they do wear out often, but in the Sprint Car world, money doesn't seem to be an issue.

No they are NOT 1100 alloy. But they are not anything special either.

Evan
04-14-2010, 05:32 PM
The difference between 6061-T6 and 1100 aluminum is about 35,000 psi tensile. That is a big difference and seems to rule out brakes. There are uses for aluminum sleeve bearings. They are widely used in fractional hp electric motors.

pcarpenter
04-14-2010, 06:02 PM
Yeah...and imagine a sleeve bearing cast as described with carbide mixed in. Now you have to use a diamond or cbn to machine this piece to tolerance...a piece of bubblegum with rocks mixed in.

I sure wish the OP would pipe up with the purpose of this "mixture". Starting to wonder if this is a trolling expedition.

Paul