[thasan]

hi guys,
i am looking for an electrodeposition of tungsten with as high purity as possible. is there any work that i can refer to??

ALSO,
does anybody know whether it is possible by some ways to electrodeposit tungsten from tungsten salts (e.g. Na2W04) without induced co-deposition (with e.g. NiSO4)?? then i can try to modify this recipe to get what i want
 

cheers,
TH

[Garneck]

I have a feeling I did that once. When I get home, I'll check through my stuff and I will tell you - of course if I find those materials.

[Garneck]

Ok, I deposited tungsten with nickel on metals. Maybe you could modify the bath like this to deposit only tungsten:

- sodium tungstate (80 g/L)
- disodium citrate (60 g/L)
- borates & phosphates (5-10 g/L)
- ammonia (to reach pH of 8,5)
- additives (dodecyl sulfate)

Deposition at temperature of 65^oC

[thasan]

hi garnek,
thanx a lot for answering.
but could you please tell me how much tungsten by weight% you got? the highest we have got is around 38 weight% and the film is not very strong...

** oh, and where is your nickel??

[Garneck]

I modified the mixture so there's no nickel in it. In its original form it contained 2,5 g/L of some nickel salt (it doesn't say which one in the text I have)

[thasan]

oh, thats really surprising. because you should need Fe, Ni or Cr for co deposition with W. Anyway, I just did an EDS on my newest plating and got around 35 %at which is not that bad.
But still, a looong way to go!! I have done all these in our clean room temperature till now. maybe i will increase the temp a more today...
thanks for your help though

[AWK]

http://www.springerlink.com/content/gnr082q41p10l5k0/