improving the density of tungsten

kafri09

hey all.

i am making a sample of bulk tungsten.
but i am getting only about 84% denstiy...

can anyone suggest a mathod of improving it?
i do not want to change my sintering process so the method should be after i get the bulk...

so... anyone can suggest a process to go from 84% bulk to about 95%+

(i am thinking of electric current or somthing like that...)

any reading materials on the subject would be great....

thanks!

litup

Are you refining it from tungsten ore? What kind of contaminants are left in the mix? You already know how hot tungsten has get to melt so it will for sure be energy intensive if all you have in your kit are thermal techniques.

notinthebox

Try melting it the shape of a long rod. Melt it slow and long. Cut off the top and bottem

Enthalpy

And what shall be the crucible material for molten tungsten, please?

Enthalpy

Do I remember that tungsten is compacted by sintering?
Wikipedia should bring some details.

Anyway, all alloys are compacted after melting, sometimes to get their normal mechanical properties, sometimes just to get a reasonable density. It parts can't be laminated, extruded... they undergo processes like isostatic compression. If not, they stay too weak.

0xDEADBEEF

Floating zone melting is an option I guess. A vertical tungsten bar can suspend itself, but I guess you wouldn't ask if you had the appropriate oven. Can't you just buy it from Goodfellow?

notinthebox

Can you give us some more info?
1 Is this for home or a commercial product?
2 what is its shape
3 are you making more then one at a time
4 Are you handy and safety minded?
5 can you make or get equipment
6 what is the weight of the end product
7 what size is it
8 what is the mold made of
9 what temp are you heating it to now
10 do you have a work shop now