Experimental and theoretical estimation of radiopacity of miniature titanium nickelide samples with micrometer Ti- and Ta-based coatings

We have analyzed the prospects of using micrometer tantalum-containing coatings for effective increase of radiopacity of miniature metal articles used in endoscopic surgery. We have tested the radiopacity of Ta and Ti–Ta coatings 1 – 2 $\mu$m in thickness formed on the surface of TiNi alloy wire samples made with a diameter of 152 $\mu$m. We consider here comparative results of calculations (from the values of X-ray attenuation coefficient) and experimental characteristics of the radiopacity of coating materials, obtained by the radiographic method on an angiographic setup. It is shown that the presence of Ti$_{60-70}$Ta$_{40-30}$ coatings 1 – 2 $\mu$m thick on a TiNi alloy wire surface doubles the radiopacity of the material. We have analyzed the variation of radiopacity of TiNi samples depending of the tantalum concentration in the coating using basic angiographic modes of recording.