Cai Cuiling, Wang Xinyu, Li Binbin, Dong Kuo, Shen Ying, Li Zhi, Shen Linyi
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China.
Biomedical Materials and Engineering Research Center of Hubei Province, Wuhan University of Technology, Wuhan 430070, China.
ACS Omega. 2021 May 3;6(19):12831-12840. doi: 10.1021/acsomega.1c01205. eCollection 2021 May 18.
The effect of sintering atmosphere (air and Ar) and temperature (1100, 1200, 1300 °C) on the microstructure, mechanical properties, and bioactivity of hydroxyapatite/tantalum (HA/Ta) composites were systematically investigated by pressureless sintering of the mixture of HA and Ta powders. It shows that the sintering atmosphere greatly impacts the phase composition and microstructure of the HA/Ta composites. The higher diffusion of atoms promotes shrinkage and causes deeper reaction fusion between the HA matrix and Ta, which improved the interfacial binding of the HA/Ta composites. The refined grain structure and improved interfacial binding obtained within the Ar atmosphere compared to the air atmosphere benefit the mechanical properties. The maximum bending strength and shrinkage observed for the composites sintered at 1300 °C in the Ar atmosphere are 27.24 MPa and 6.65%, respectively. The cell counting kit-8 (CCK-8) method was used to investigate the in vitro cytocompatibility of HA/Ta composites. The results revealed that the HA/Ta composites sintered with different conditions have no cytotoxicity. The simulated body fluid (SBF) soaking results showed that all of the studied composites possess desirable bioactivity, as demonstrated by their ability to form calcium-deficient carbonate apatite layer on the surfaces. For composites sintered at 1300 °C, the surface apatite layer coverage of the composites obtained in the Ar atmosphere was increased by 139.7% than the ones obtained in air, which confirmed an enhanced bioactive mineralization ability. The results indicated that the HA/Ta composites sintered at 1300 °C in Ar possess desirable mechanical properties and bioactivity. This work opens up the new possibility for preparing HA-based composites and is of great value in biomedical applications.
通过对羟基磷灰石/钽（HA/Ta）粉末混合物进行无压烧结，系统研究了烧结气氛（空气和氩气）和温度（1100、1200、1300℃）对HA/Ta复合材料微观结构、力学性能和生物活性的影响。结果表明，烧结气氛对HA/Ta复合材料的相组成和微观结构有很大影响。原子的较高扩散促进了收缩，并导致HA基体与Ta之间更深的反应融合，从而改善了HA/Ta复合材料的界面结合。与空气气氛相比，在氩气气氛中获得的细化晶粒结构和改善的界面结合有利于力学性能。在氩气气氛中于1300℃烧结的复合材料观察到的最大弯曲强度和收缩率分别为27.24MPa和6.65%。采用细胞计数试剂盒-8（CCK-8）法研究了HA/Ta复合材料的体外细胞相容性。结果表明，不同条件下烧结的HA/Ta复合材料均无细胞毒性。模拟体液（SBF）浸泡结果表明，所有研究的复合材料都具有良好的生物活性，其表面能够形成缺钙碳酸磷灰石层。对于在1300℃烧结的复合材料，在氩气气氛中获得的复合材料表面磷灰石层覆盖率比在空气中获得的提高了139.7%，这证实了生物活性矿化能力的增强。结果表明，在氩气中于1300℃烧结的HA/Ta复合材料具有良好的力学性能和生物活性。这项工作为制备基于HA的复合材料开辟了新的可能性，在生物医学应用中具有重要价值。
