Hello All,
I’ve got an interesting friction related issue that I’m trying to solve. So there are two sliding surfaces where contact area is 1292 sq mm / 2 sq in and they move back and forth hand operated, so slowly. First design both were EN-AW 2007 Aluminum and no anodizing or any kind of surface treatment. Just lubrication between, tried different types of oils and greases. Problem is that metal to metal contact happens and scratches and wear appear. Both contact surfaces were grind by 400 grit sand paper on top of glass so surface is very smooth.
So the question is, is there any chance to get untreated AL to AL surfaces make work together as a slider with any lubricant between? I was thinking that could any of the grit from sandpaper embed to the AL causing scratches and wear? Or maybe too fine surface and there is no crevices for the lubrication to stay to prevent metal to metal contact..
Second attempt was that I changed the other part to tool steel and tempered it. Also grind it to smooth with the same method. Same scratching and wear appear but on plus side it slides easier.
Unfortunately it is not possible to add any friction reducing part like UHMWPE or PTFE between, so that is not an option. I was thinking of what surface treatment/coatings methods available that could reduce friction but not add thickness? Nicasil, anodizing, ptfe coating etc? If it could be possible to manage without separate lubricants, that would be the best.
If coating method increase thickness, is it known beforehand as then I would need to take that in account in the design. Currently it basically doesn’t have any clearance between the two or max. 0.01mm.
Suggestions / thoughts? Thank you in advance.
I’ve got an interesting friction related issue that I’m trying to solve. So there are two sliding surfaces where contact area is 1292 sq mm / 2 sq in and they move back and forth hand operated, so slowly. First design both were EN-AW 2007 Aluminum and no anodizing or any kind of surface treatment. Just lubrication between, tried different types of oils and greases. Problem is that metal to metal contact happens and scratches and wear appear. Both contact surfaces were grind by 400 grit sand paper on top of glass so surface is very smooth.
So the question is, is there any chance to get untreated AL to AL surfaces make work together as a slider with any lubricant between? I was thinking that could any of the grit from sandpaper embed to the AL causing scratches and wear? Or maybe too fine surface and there is no crevices for the lubrication to stay to prevent metal to metal contact..
Second attempt was that I changed the other part to tool steel and tempered it. Also grind it to smooth with the same method. Same scratching and wear appear but on plus side it slides easier.
Unfortunately it is not possible to add any friction reducing part like UHMWPE or PTFE between, so that is not an option. I was thinking of what surface treatment/coatings methods available that could reduce friction but not add thickness? Nicasil, anodizing, ptfe coating etc? If it could be possible to manage without separate lubricants, that would be the best.
If coating method increase thickness, is it known beforehand as then I would need to take that in account in the design. Currently it basically doesn’t have any clearance between the two or max. 0.01mm.
Suggestions / thoughts? Thank you in advance.
