Preliminary Study on the Seizure Trend of a MOM-THP with Self-directed Balls

This work continues the approach of one of our topics relating to a MOM-THP （metal on metal-total hip prostheses） with self-directed movement balls. Experiments revealed a certain seizure in some strain conditions. Laboratory trials for balls/plane Hertzian contacts have been restarted in order to determine seizure behaviour depending on the roughness of the flat area. The trials have been carried out in BSF （body simulated fluid） lubrication conditions, much closer to the real operating conditions up against the initial tests with distilled water. Seizure burdens to different loadings and contact surfaces roughness influence over the seizure burden have been determined. Even though the minimum value of the wear must be the same with the minimum value of the surfaces roughness, given the experimental conditions, it came out from the trials results on wear that the lowest level of wear is acquired at a certain value of roughness, not at the lowest level of roughness.