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Lubricity of cobalt 2
- Thread starter tomwalz
- Start date
You picked a hard one as most of the latest information about cobalt is under lock and key.
You might find some properties on cobalt
At one time there was an very informative booklet called "COBALT" published by:
"Union Miniere” of Belgium, who at one time controlled most of the cobalt used in the West. A lot of technical libraries received this booklet and some still may have it in the stacks or better yet on microfilm.
They have a new name Umicore at:
You could check with them to see if they still have all the information they gathered on Cobalt and if not where is it located.
You might find some properties on cobalt
At one time there was an very informative booklet called "COBALT" published by:
"Union Miniere” of Belgium, who at one time controlled most of the cobalt used in the West. A lot of technical libraries received this booklet and some still may have it in the stacks or better yet on microfilm.
They have a new name Umicore at:
You could check with them to see if they still have all the information they gathered on Cobalt and if not where is it located.
- Thread starter
- #3
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1
- #5
Smithells Metals Reference Book, 7th Edn., has a bit of info.
Table 25.1 has static friction data for very clean pure metals (self-mated) in both vacuum and in air. Cobalt was lowest for each condition, e.g., 0.3 in air vs. 0.4 for chromium, which was next lowest.
Figure 25.2 ‘Tendency of metal couples to adhere together’ ranks pairs of 19 different metals from 1 – least adhesion, best wear resistance to 4 – most adhesion, worst wear. For most combinations, Co is about the same as Cr, Ni & Fe. It is slightly better vs. Al, Au, In & Ti. Worse than Cr vs. Cu, Sn & Zr.
Adhesion is greatest for those metals sharing the same crystal structure and/or forming intermetallics. Also, the thickness of the surface oxide matters – stainless steels and nickel-base alloys having very thin films, do not have good adhesive wear resistance and can gall. As the chemistry of Co is similar to that of Ni, similar behavior is likely.
A search for galling resistance may help.
You might also try suppliers of Co plating chemicals as to the deposit properties.
Table 25.1 has static friction data for very clean pure metals (self-mated) in both vacuum and in air. Cobalt was lowest for each condition, e.g., 0.3 in air vs. 0.4 for chromium, which was next lowest.
Figure 25.2 ‘Tendency of metal couples to adhere together’ ranks pairs of 19 different metals from 1 – least adhesion, best wear resistance to 4 – most adhesion, worst wear. For most combinations, Co is about the same as Cr, Ni & Fe. It is slightly better vs. Al, Au, In & Ti. Worse than Cr vs. Cu, Sn & Zr.
Adhesion is greatest for those metals sharing the same crystal structure and/or forming intermetallics. Also, the thickness of the surface oxide matters – stainless steels and nickel-base alloys having very thin films, do not have good adhesive wear resistance and can gall. As the chemistry of Co is similar to that of Ni, similar behavior is likely.
A search for galling resistance may help.
You might also try suppliers of Co plating chemicals as to the deposit properties.
- Thread starter
- #6
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1
- #7
CalvinKelly
Materials
At elevated temperatures high cobalt alloys form a scale which is somewhat lubricious. That is, at red heat cobalt alloys are less likely to gall than are nickel base alloys.
James Kelly
James Kelly
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