ABSTRACT
In surface-roughened metallic implant materials, the topography, chemistry and energy of the surfaces play an important role for the cell and tissue attachment. The highly reactive commercially pure metals niobium, tantalum and titanium were analysed after microblasting (with Al2O3 powder and consecutive shot-peening with ZrSiO2), and after additional reactive ion etching (RIE, with CF4). Scanning electron microscopy in combination with energy-dispersive X-ray analysis and surface roughness measurements showed, for all microblasted surfaces, a heterogeneous roughening (Ra about 0.7 microm), and a contamination with blasting particles. RIE resulted in a further roughening (Ra about 1.1 microm), and a total cleaning from contaminations, except for traces of aluminium. Determination of surface energy by dynamic contact angle measurements showed an increase in surface energy after microblasting, which further increased after RIE, most pronounced for commercially pure niobium. In conjunction with superior electrochemical properties, this makes niobium and tantalum promising candidates for implant purposes, at least equal to the generally used titanium.
ABSTRACT
A method of nondestructive depth profiling in near surface regions of solids is described. Models have been discussed from which algorithms for evaluation of measured data are obtained. The algorithms, based on standard profiles with free parameters, have been adjusted to the data resulting from angle resolved XPS (ARXPS) by means of least squares fits. Depth profile analyses and segregation studies were performed on Pt-Ni and Fe-S specimens.
