Hydroxyapatite (HA) is widely used in scaffolds due to its high similarity in the composition to natural bone. However, the weak and fragile characteristics of synthetic HA limit its application. The strength of HA can be increased by the incorporation of alumina (AlO) to obtain composites with extraordinary compressive strength and biocompatibility. HA-AlO composites with different ratios were prepared by Vat photopolymerization 3D printing, and their shrinkage, porosity, phase composition and biocompatibility were systematically investigated. In addition, the Diamond structure of the scaffold was chosen to achieve the trade-off relationship between compressive strength and porosity. The results suggest that the HA-AlO composite with 20 vol% HA possesses the maximum compressive strength and 60 vol% HA has optimal biocompatibility. A compositional gradient scaffold from 60 vol% HA and 20 vol% HA was proposed to satisfy different needs of the different parts in scaffold for biocompatibility and compressive strength. The HA-AlO gradient scaffold achieves a preferable compressive strength of 13.7 MPa while possessing gradient biocompatibility.

中文翻译：

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通过 Vat 光聚合 3D 打印功能分级的 HA-Al2O3 三周期最小表面支架

羟基磷灰石（HA）由于其成分与天然骨高度相似而广泛应用于支架中。然而，合成HA的弱和易碎的特性限制了其应用。通过掺入氧化铝 (Al2O) 可以提高 HA 的强度，以获得具有非凡抗压强度和生物相容性的复合材料。采用Vat光聚合3D打印技术制备了不同配比的HA-Al2O复合材料，并系统研究了其收缩率、孔隙率、相组成和生物相容性。此外，支架的金刚石结构的选择是为了实现抗压强度和孔隙率之间的权衡关系。结果表明，HA-Al2O 复合材料中 HA 含量为 20 vol% 时具有最大的抗压强度，HA 含量为 60 vol% 时具有最佳的生物相容性。提出了一种由60 vol% HA和20 vol% HA组成的梯度支架，以满足支架不同部位对生物相容性和抗压强度的不同需求。 HA-Al2O3梯度支架实现了13.7 MPa的较好抗压强度，同时具有梯度生物相容性。