Some implants have approximately a lifetime of 15 years. The femoral stem,
for example, should be made of 316L/316LN stainless steel. Fretting corrosion,
friction under small displacements, should occur during human gait, due to
repeated loadings and un-loadings, between stainless steel and bone for
instance. Some experimental investigations of fretting corrosion have been
practiced. As well known, metallic alloys and especially stainless steels are
covered with a passive film that prevents from the corrosion and degradation.
This passive layer of few nanometers, at ambient temperature, is the key of our
civilization according to some authors. This work is dedicated to predict the
passive layer thicknesses of stainless steel under fretting corrosion with a
specific emphasis on the role of proteins. The model is based on the Point
Defect Model (micro scale) and an update of the model on the friction process
(micro-macro scale). Genetic algorithm was used for finding solution of the
problem. The major results are, as expected from experimental results, albumin
prevents from degradation at the lowest concentration of chlorides; an
incubation time is necessary for degrading the passive film; under fretting
corrosion and high concentration of chlorides the passive behavior is
annihilated
