SPS烧结制备生物活性镁黄长石陶瓷

钙硅基生物陶瓷具有良好的生物活性和细胞相容性, 在生物医疗领域具有广阔的发展前景。但是其粉体烧结性能差的缺点导致很难获得致密的陶瓷材料, 阻碍了其应用的进程。本研究采用化学共沉淀法制备了纯度高且烧结活性好的镁黄长石粉体, 然后采用放电等离子烧结技术(SPS)制备了镁黄长石陶瓷材料。通过X射线衍射(XRD)和扫描电子显微镜(SEM)表征了样品的组成结构和显微形貌, 并通过阿基米德法和模拟体液浸泡法分析了镁黄长石陶瓷样品的致密度和生物活性。研究结果表明, 采用SPS技术在1170℃、70 MPa保温5 min条件下可获得致密度超过99%的镁黄长石陶瓷材料。在模拟体液中浸泡3 d, 陶瓷样品表面出现磷酸盐的沉积, 浸泡7 d后生成了类骨羟基磷灰石, 说明SPS技术制备的致密镁黄长石生物陶瓷具有良好的诱导沉积类骨磷灰石能力。

Spark Plasma Sintering of Bioactive Ca2MgSi2O7 Ceramics

The bio-ceramics based on Ca and Si have wide development prospect in biomedical, which is attributed to their outstanding bioactivity and cytocompatibility. However, how to improve its sinterability is a key problem to be solved. In this study, pure Ca₂MgSi₂O₇ powders were prepared via a co-precipitation method, and then were sintering by spark plasma sintering (SPS) technique. The phase and the morphology of the resulting products were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. The relative density and the bioactivity were also investigated by Archimedean method and simulated body fluid (SBF) soaking method, respectively. Experimental results showed that the Ca₂MgSi₂O₇ ceramics with density of about 99% could be achieved by spark plasma sintering at 1170℃ for 5 min under 70 MPa. After soaking in the simulated body fluid for 3 d, phosphate precipitation was observed on the surface of the ceramics, while bone-like hydroxyapatite was formed until 7 d soaking, indicating that the Ca₂MgSi₂O₇ ceramics prepared by SPS have good bioactivity to induce the sedimentation of bone-like hydroxyapatite.