Titanium alloys have been widely used as biomaterials, especially for orthopedic prostheses and dental implants, but these materials have Young's modulus almost three times greater than human cortical bones. Because of this, new alloys are being produced for the propose of decreasing Young's modulus to achieve a more balanced mechanical compatibility with the bone. In this paper, it is reported the development of Ti-25Ta alloys as a base material, in which was introduced zirconium, with concentration varying between 0 and 40 wt%, with the aim of biomedical applications. The alloys were prepared in an arc-melting furnace. The microstructural analysis was performed by x-ray diffraction as well as optical and scanning electron microscopy. Selected mechanical properties were analyzed by microhardness and Young's modulus measurements, and cytotoxicity analysis by indirect test. X-ray measurements revealed the presence of α″ phase in the alloy without zirconium; α″ + β phases for alloys with 10, 20, and 30 wt% of zirconium, and β phase only for the alloy with 40 wt% of zirconium. These results were corroborated by the microscopy results. The hardness of the alloy was higher than that of cp-Ti due to the actions of zirconium and tantalum as hardening agents. The Young's modulus decreases with high levels of zirconium due to the stabilization of the β phase. The cytotoxicity test showed that the extracts of studied alloys are not cytotoxic for osteoblast cells in short periods of culture.

中文翻译：

---

Ti-25Ta-Zr铸态合金的制备，结构，微观结构，力学和细胞毒性表征。

钛合金已被广泛用作生物材料，尤其是用于矫形假体和牙科植入物，但是这些材料的杨氏模量几乎是人类皮质骨的三倍。因此，为了降低杨氏模量以实现与骨骼更平衡的机械相容性，正在生产新的合金。在本文中，据报道以生物医学应用为目的，开发了以Ti-25Ta合金为基础的材料，其中引入了锆，其浓度在0至40 wt％之间变化。合金是在电弧熔炉中制备的。显微结构分析是通过X射线衍射以及光学和扫描电子显微镜进行的。通过显微硬度和杨氏模量测量分析选定的机械性能，通过间接测试进行细胞毒性分析。X射线测量显示不含锆的合金中存在α''相。对于含10、20和30 wt％的锆的合金，α“ +β相；对于含40 wt％的锆的合金，仅β相。显微镜结果证实了这些结果。由于锆和钽作为硬化剂的作用，合金的硬度高于cp-Ti。由于β相的稳定，锆含量高时，杨氏模量降低。细胞毒性试验表明，所研究合金的提取物在短期培养中对成骨细胞没有细胞毒性。β相仅适用于含40 wt％锆的合金。显微镜结果证实了这些结果。由于锆和钽作为硬化剂的作用，合金的硬度高于cp-Ti。由于β相的稳定，锆含量高时，杨氏模量降低。细胞毒性试验表明，所研究合金的提取物在短期培养中对成骨细胞没有细胞毒性。β相仅适用于含40 wt％锆的合金。显微镜结果证实了这些结果。由于锆和钽作为硬化剂的作用，该合金的硬度高于cp-Ti。由于β相的稳定，锆含量高时，杨氏模量降低。细胞毒性试验表明，所研究合金的提取物在短期培养中对成骨细胞没有细胞毒性。