Hydrogen absorption of titanium and nickel-titanium alloys during long-term immersion in neutral fluoride solution

✍ Scribed by Ken'ichi Yokoyama; Toshio Ogawa; Kenzo Asaoka; Jun'ichi Sakai

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 350 KB
• Volume: 78B
• Category: Article
• ISSN: 1552-4973
• DOI: 10.1002/jbm.b.30485

✦ Synopsis

Abstract

Hydrogen absorption of biomedical titanium and Ni‐Ti alloys in a neutral fluoride (2.0% NaF) solution for up to 10,000 h at 37°C has been evaluated by means of hydrogen thermal desorption analysis. For α titanium (commercial pure titanium), the amount of absorbed hydrogen was, at most, 10–30 mass ppm, and the corrosion product and hydride formation were revealed on the surface of the specimen by X‐ray diffraction analysis. Ni‐Ti superelastic alloy absorbed ∼150 mass ppm of hydrogen, which was probably sufficient to result in the pronounced degradation of the mechanical properties, although corrosion was hardly observed. In contrast, hydrogen absorption of α‐β titanium (Ti‐6Al‐4V) and β titanium (Ti‐11.3Mo‐6.6Zr‐4.3Sn) alloys was negligible, although general corrosion was observed. The results of the present study indicate that the susceptibility of titanium and Ni‐Ti alloys to hydrogen absorption in the neutral fluoride solution is different from that in the acidic fluoride solution reported previously. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006