Orange peel on metal surfaces 2

[Eggbert]

Hi,
Working for a nonwoven abrasive company we occasionally come up against our products causing orange peel effects on metal surfaces.
This happens mostly on Aluminium, Titanium & Brass which we rarely know the composition of.
We know it has to do with the grain size on the metal's surface but, as none of us are metallurgists, we don't know the exact mechanism / trigger for the phenomenon.
Could someone let us know why this happens and how to stop it happening?

Ta

Eggbert

 

[mcguire]

Orange peel is observed when the grains are so large that the slip planes of deformation exit the surface and can be seen as ridges. You can't stop a metal from having its characteristic slip mode, so the common solution is to have finer, randomly oriented grains so that the surface relief is not visible.
There could be more complicated solutions, but this is the common one.

 

[EdStainless]

The other solution, more from your point of view, is to use a more rigid and agressive abrasive. When the polish can follow the grain contour it will highlight the grains.

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Corrosion never sleeps, but it can be managed.

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