Improvement of Anti-Wear Function of Pivot Bearing for a Centrifugal Blood Pump (Part 1): Wear Mechanisms in Spinning Motion

摘要

How the contact areas of the plates of ultra-high-molecular weight polyethylene (UHMWPE) and the same material but cast in advance with γ-ray on which an alumina ceramic hemisphere, 3 mm diameter, is pressed at a load of 10 N, change their profiles with load time, are studied experimentally in creep tests and spinning contact wear tests. The spinning contact wear tests are carried out on condition that the alumina ceramic hemisphere revolves at 2,000 rpm. It is found that the profile of the contact area of UHMWPE, unilaterally deformed and brought into a hemisphere concave according to the shape of the hard male pivot during load test, turns out to be a pattern of letter W when the elastic recovery completes after load is removed.