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  for Metal Finishing since 1989
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Aluminum galling problem

I am a product designer in Finland. Lets see if someone can give me some tips or guide me to a solution.

My problem is the following:

I have two Al-6082 surfaces sliding against each other under high stresses, what leads to a severe galling that I would like to avoid. On the other hand, I would not like to diminish the friction coefficient with a lubricant because it would lead to a sharp increment of the stresses. Do you know how this could be solved? Is there a rule of thumb to avoid galling? Do you think that it could be avoided using a different Al alloy? Where could I get more information about galling? (website, book) I am also looking for a table with friction coefficients for different Al alloys pairs, do you know where I could find such a table? (I have just found very simple ones with few materials)

I have read that growing the Al natural oxide layer might avoid it. Do you know how could I estimate the layer thickness that would avoid it?

Thank you very much.

Carlos del Corral
Product development engineer - Porvoo, Finland
2004

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Dear sir,

Please try to hard anodize sliding surface and seal or impregnate the pore of oxide layer with silicon or molybdenum sulfide.

Hadi Khosravi
- Tehran, Iran
2004