One cause of the excellent hard‐tissue compatibility of Ti and Ti alloys compared with other metals is their ability to form calcium phosphate in biological environments. This is confirmed by many studies, although the formation mechanism has not been completely elucidated. In this study, to elucidate the initial formation kinetics of calcium phosphate on Ti in the human body, Ti was immersed in a simulated body fluid, Hanks' solution, for 10⁰–10⁶ s, followed by precise characterization using XPS. Ti specimens immersed in diluted Hanks' solutions were also characterized. The results reveal that phosphate ions are preferentially adsorbed and are incorporated onto the Ti surface in 10⁰–10² s. This reaction is slow, and the apparent thickness of the surface layer is almost constant as 5.2 nm until 10² s. However, both calcium and phosphate ions are then rapidly incorporated, and calcium phosphate is formed after 10³ s. The amounts of both calcium and phosphate increase with the logarithm of time because calcium and phosphate ions react directly with the Ti surface until 10⁵ s. Other elements contained in Hanks' solution are not incorporated, calcium phosphate being formed preferentially. The incorporation of calcium is faster than that of phosphate, and the [Ca]/[P] ratio increases with the logarithm of time after 10³ s. However, the chemical state of surface oxide film itself on Ti does not changed by immersion in Hanks' solution. The formation kinetics of calcium phosphate on Ti in a simulated body fluid are clearly revealed by this study.

中文翻译：

---

用XPS表征Hanks溶液中钛上磷酸钙的初始形成动力学

与其他金属相比，Ti和Ti合金具有出色的硬组织相容性的原因之一是它们在生物环境中形成磷酸钙的能力。尽管尚未完全阐明其形成机理，但许多研究证实了这一点。在本研究中，为了阐明磷酸钙在人体上最初的形成动力学，将钛浸入汉克斯溶液的模拟体液中10 ⁰ –10 ⁶ s，然后使用XPS进行精确表征。还对浸入稀释的汉克斯溶液中的钛样品进行了表征。结果表明，磷酸根离子被优先吸附，并以10 ⁰ –10 ^2的速度结合到Ti表面上s。该反应是缓慢的，并且表面层的表观厚度直到10 ² s几乎恒定为5.2nm 。但是，钙离子和磷酸根离子随后会迅速结合，并且在10 ³ s后会形成磷酸钙。钙和磷酸根的量都随时间的对数增加，因为钙和磷酸根离子直接与Ti表面反应直到10 ⁵ s。汉克斯溶液中所含的其他元素未掺入，优先形成磷酸钙。钙的掺入比磷酸盐的掺入更快，并且[Ca] / [P]比随10 ³之后的时间的对数增加而增加。s。但是，Ti上的表面氧化膜本身的化学状态不会因浸入Hanks溶液而改变。这项研究清楚地揭示了模拟体液中钛上磷酸钙的形成动力学。