Li Feng, Jiang Xiaosong, Shao Zhenyi, Zhu Degui, Zhu Minhao
School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, China.
Department of Material Engineering, Chengdu Technological University, Chengdu 611730, China.
Materials (Basel). 2018 Apr 16;11(4):608. doi: 10.3390/ma11040608.
Biomaterial composites made of titanium and hydroxyapatite (HA) powder are among the most important biomedicalmaterials due to their good mechanical properties and biocompatibility. In this work, graphene-reinforced titanium matrix/nano-hydroxyapatite nanocomposites were prepared by vacuum hot-pressing sintering. The microstructure and mechanical properties of graphene-reinforced titanium matrix/nano-hydroxyapatite nanocomposites with different graphene content were systematically investigated. Microstructures of the nanocomposites were examined by X-ray diffraction (XRD), back scattered electron imaging (BSE), scanning electron microscope (SEM) equipped with energy dispersive spectrometer (EDS), electron probe microanalyzer (EPMA), and transmission electron microscope (TEM). The mechanical properties were determined from microhardness, shear strength, and compressive strength. Results showed that during the high-temperature sintering process, complex chemical reactions occurred, resulting in new phases of nucleation such as Ca₃(PO₄)₂, TiP, and Ti₃O.The new phases, which easily dropped off under the action of external force, could hinder the densification of sintering and increase the brittleness of the nanocomposites. Results demonstrated that graphene had an impact on the microstructure and mechanical properties of the nanocomposites. Based on the mechanical properties and microstructure of the nanocomposites, the strengthening and fracture mechanisms of the graphene-reinforced titanium matrix/nano-hydroxyapatite nanocomposites with different graphene content were analyzed.
由钛和羟基磷灰石（HA）粉末制成的生物材料复合材料因其良好的力学性能和生物相容性而成为最重要的生物医学材料之一。在这项工作中，通过真空热压烧结制备了石墨烯增强钛基/纳米羟基磷灰石纳米复合材料。系统研究了不同石墨烯含量的石墨烯增强钛基/纳米羟基磷灰石纳米复合材料的微观结构和力学性能。通过X射线衍射（XRD）、背散射电子成像（BSE）、配备能量色散谱仪（EDS）的扫描电子显微镜（SEM）、电子探针微分析仪（EPMA）和透射电子显微镜（TEM）对纳米复合材料的微观结构进行了检测。从显微硬度、剪切强度和抗压强度测定力学性能。结果表明，在高温烧结过程中发生了复杂的化学反应，导致了Ca₃(PO₄)₂、TiP和Ti₃O等新的成核相。这些新相在外力作用下容易脱落，会阻碍烧结致密化并增加纳米复合材料的脆性。结果表明，石墨烯对纳米复合材料的微观结构和力学性能有影响。基于纳米复合材料的力学性能和微观结构，分析了不同石墨烯含量的石墨烯增强钛基/纳米羟基磷灰石纳米复合材料的强化和断裂机制。
