Effects of sintering and zirconmullite doping on nanostructural vacancies of bovine hydroxyapatite by positron techniques |
| |
Authors: | Leyla Nur Akay Cevriye Kalkandelen Necmettin Akti Merve Sazimet Sengul Cumali Tav Ugur Yahsi Ziya Engin Erkmen |
| |
Affiliation: | 1. Department of Physics, Faculty of Science, Marmara University, Kadikoy, Istanbul, Turkey;2. Department of Biomedical Devices Technology, Vocational School of Technical Sciences, Istanbul University-Cerrahpasa, Istanbul, Turkey;3. Metallurgical and Materials Engineering Department, Faculty of Engineering, Marmara University, Maltepe, Istanbul, Turkey |
| |
Abstract: | In this study, the nanostructural vacancy behavior of bovine derived hydroxyapatite (BHA) doped with powder zirconmullite (ZM) contents of 5, 7.5, 10 and 12.5 wt.% were presented at sintering temperatures of 1000, 1100, 1200 and 1300°C. ZM-doped BHA (ZM-BHA) was characterized by X-ray diffraction and positron annihilation lifetime spectroscopy (PALS). Density and hardness behavior were measured with respect to increasing sintering temperature. PALS results indicate that the longest lifetime component τ3 of ortho-positronium (o-Ps) localized at open spaces is attributed to the vacancy site and almost constant with the ZM contents and the sintering temperatures to have a mean value of 0.680 ns (corresponding to the radius of 0.997 nm). This average value is ascribed to the OH group defects along the main crystalline line. On the other hand, the o-Ps intensity attributed to the number of vacancy sites increases almost linearly with ZM additives and sintering temperatures. The intensity is also related to the density and hardness of ZM-BHA in terms of ZM contents. |
| |
Keywords: | bovine hydroxyapatite mechanical properties positron annihilation lifetime spectroscopy (PALS) vacancy zirconmullite |
|
|