In-depth profiling of elastic residual stress and the in vivo wear mechanism of self-mating alumina hip joints

摘要: Abstract Residual (elastic) stress profiles developed in self-mating alumina heads upon long-term exposure the human body have been quantitatively determined by means of three different piezo-spectroscopic (PS) approaches available to lattice. The PS measurements, collected at exactly same area sample, included fluorescence spectroscopy (fs), Raman (rs) (in-depth resolutions both order tens μm), and cathodoluminescence (cs) resolution down nm). lateral spatial was μm, single hundredths nm for fs rs cs, respectively. Owing precise knowledge response functions space probes, deconvoluted could be obtained zone wear severity. revealed high gradients along material subsurface, “cleaned” from averaging effects related finite probe volume. subsurface field heavily worn zones entailed a surface layer under strong compression, an abrupt compressive-to-tensile transition up similar magnitude, deeper-lying region tension which ultimately relaxed unstressed bulk. opposite trend observed mildly femoral head, with moderate tensile stresses immediate weak counterbalancing compressive nature subsurface. A mechanism hip surfaces then drawn consistently newly residual profiles.