钛表面仿生制备Si-HA涂层的热力学分析

Thermodynamic Analysis of Biomimetic Si-HA Coating on Titanium

通过计算室温下含硅过饱和钙磷沉积液（SSCPS）中可能形成的各沉积相的过饱和度，对仿生制备含硅羟基磷灰石（Si—HA）的热力学条件进行了分析。结果表明：羟基磷灰石（HA）过饱和度最大；且当pH〈8时，硅不具备以偏硅酸盐形式存在的热力学条件，从而表明SSCPS具备仿生制备Si—HA涂层的热力学可能性。在SSCPS中通过浸泡，在钛表面仿生制备了Si—HA涂层，其Si含量在0．14at％～1．14at％，实验验证了热力学分析的正确性：还跟踪了仿生沉积过程pH值变化。

The formation thermodynamics conditions of Si-substituted hydroxyapatite （Si-HA） from silicon-containing supersaturated calcium phosphate solutions （SSCPS） have been analyzed by the calculation of the supersaturations for various phases potentially precipitated at room temperature. The results have showed that the HA has the largest supersaturation and the silicon has no thermodynamic potential to precipitate in the form of CaSiO3 from SSCPS when the pH value is less than 8, which suggests that the SSCPS can provide thermodynamic priority for the biomimetic formation of Si-HA coating on titanium substrate. By experiment, the biomimetic Si-HA coatings with different Si contents （0.14 at% to 1.14 at%） on titanium are produced by immersing in SSCPS, which confirmed the thermodynamic analysis results. In addition, the pH value in SSCPS during the deposition process aretaileded.