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Zirconia rolling friction coefficient
- Thread starter pagheca
- Start date
Rolling resistance and coefficient of friction are not the same thing.
Both rolling resistance and coefficient of friction are interface properties. The coefficient of friction of something against steel will be very different from its mu on Teflon.
Since you haven't told us the second material, your question, as posed, is unanswerable.
Both rolling resistance and coefficient of friction are interface properties. The coefficient of friction of something against steel will be very different from its mu on Teflon.
Since you haven't told us the second material, your question, as posed, is unanswerable.
- Thread starter
- #4
Thanks for the replies.
Reidh: Unfortunately I haven't yet a sample of the material. I'll do extensive tests but, as I have a small budget, I want to understand better before to buy.
MintJulep: right, the other material is hardened stainless steel. What I need to know is how Zirconia/steel rolling resistance (usually indicated as "rolling friction coefficient") matches respect to steel/steel coefficient. Lower? Higher? 3 times? 5 times?
Regards,
Reidh: Unfortunately I haven't yet a sample of the material. I'll do extensive tests but, as I have a small budget, I want to understand better before to buy.
MintJulep: right, the other material is hardened stainless steel. What I need to know is how Zirconia/steel rolling resistance (usually indicated as "rolling friction coefficient") matches respect to steel/steel coefficient. Lower? Higher? 3 times? 5 times?
Regards,
The geometry plays a big roll, and at some point the loading effects the geometry.
Example - ball bearing contact depends in part on ratio of race and ball curvature to form a contact ellipse. That ratio is one of the key elements in the speed rating (temp generation) of a ball bearing. Rolling and sliding coexist in the contact ellipse. If there is lubrication and conditions are right for lubrication to establish elastohydrodynamic lubrication then there may be NO metal to metal contact, and lube shear dominates. Bigger load results in larger ellipse.
A cylindrical roller bearing deforms the surface it bears on, and itself. Even gorgeous roller geometry is probably slightly conical so the roller will try to pull off to the side of the road. And the roller will sink into the surface like a Corvette driving on beach sand.
Example - ball bearing contact depends in part on ratio of race and ball curvature to form a contact ellipse. That ratio is one of the key elements in the speed rating (temp generation) of a ball bearing. Rolling and sliding coexist in the contact ellipse. If there is lubrication and conditions are right for lubrication to establish elastohydrodynamic lubrication then there may be NO metal to metal contact, and lube shear dominates. Bigger load results in larger ellipse.
A cylindrical roller bearing deforms the surface it bears on, and itself. Even gorgeous roller geometry is probably slightly conical so the roller will try to pull off to the side of the road. And the roller will sink into the surface like a Corvette driving on beach sand.
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