ball cratering

Please try the Plint&Partners web site ( As far as I know, they are specialist about microfriction equipment. Two years ago, I used their microfriction machine for my studies and as a result, I took very succesful results from my experiments.

Regards,

Try this web site:

Susana,
Try CSEM website. They have something called as a CALO test equipment which is used to find the thickness of the PVD coatings. It makes use of a carbide ball and a flat coated surface. The ball rotates against the coated surface producing a crater. The diameters of the inner uncoated surface and the coated surface give the measure of coating thickness. I don't know if this is what you were looking for, but thought this could be some use to you.
Cheers
Satish

Does anyone know if there is a relationship between fretting corrosion and contact pressure in two microscopically sliding oscillating surfaces ?

I am trying to establish some load limits for ball bearings where there is a tendency to 'false brinell' due to load fluctuations when the brg is not rotating. The application is a wind turbine blade brg.

Some manufacturers have suggested that the relationship resembles a bending fatigue S-N curve, ie. below a certain contact stress level f/b will not occur regardless of how many movement cycles are made. I dont really believe this is the case. I think low contact stresses will create the same level of damage given sufficient cycles. Any thoughts or experience ?

Gerry