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Copper tungsten

2003

Dear Sir,

We take molten copper to penetrate the sintered tungsten, but it worked out as always a not completely penetration, also not homogeneous. Ould you kindly give me a help?

Thanks a lot.

Beck Liu
- Chengdu, Sichuan, China

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I am not an expert in sintering,but your question strikes me as a bit strange because my understanding is that the tungsten powder should be copper plated before sintering.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003

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We use copper-tungsten for some EDM electrodes we buy- it's a nice material for that, as it combines heat resistance with electrical conductivity. I had always THOUGHT it was completely P/M: i.e., one started with copper and tungsten powder and formed them together using standard powder metallurgy techniques. I'd not heard of a porous tungsten preform as a precursor.

I could only recommend the obvious things- either use vacuum or a gas readily dissolved in molten copper to fill the pores in the tungsten before infiltration. Pressure techniques may be needed, wherein you use a die to force the copper into the tungsten. You may also try a lower density tungsten and then work it by rolling, forging, etc- the copper will flow out of the preform and increase the apparent tungsten concentration. Perhaps.

Good luck!

Lee Gearhart
metallurgist - E. Aurora, New York
2003

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2003

Dear Mr. Lee Gearhart,

Thanks for your help. Now we have done it, but thanks any way. Copper infiltrated tungsten will have a better performance than P/M of powder mixed by copper and tungsten as I know.

Thanks,

Beck Liu
- China