Development of Titanium Alloys with Low Elastic Modulus and High Corrosion Resistance designed on the Basis of Quantum Chemistry Theory

为了开发低弹性模量、高耐蚀性的新型钛合金，研究了Zr含量为0、20、40、60、70、80、100 at.%的Ti-Zr二元合金的密度、杨氏模量、泊松比和维氏显微硬度。主要实验结果如下：1.密度Ti-Zr二元合金的密度与成分曲线稍微正偏离连接纯Ti和纯Zr两端两点的直线基线。值得注意的是，与富Zr区域相比，富Ti区域与直线基线的偏离程度略大。铸态纯Ti和Zr的硬度分别为157 VHN和196 VHN。合金化添加量为20 at.% Zr到Ti急剧增加硬度，表明发生了大量的固溶硬化。Zr的进一步添加进一步增加了维氏硬度，在Ti-60原子%时高达约370 VHN Zr成分。当Zr与Ti合金化时，观察到类似的固溶硬化。但是，富Zr区的硬度增加幅度远小于富Ti区.纯钛的杨氏模量显著高于纯锆。Ti与Zr合金化后，杨氏模量显著降低，在Ti-60 at.%时，杨氏模量最小，约为89 GPa Zr成分。另一方面，纯钛的泊松比明显低于纯锆。Ti与Zr合金化后，材料的泊松比显著增大，在Ti-60 at.%时，材料的泊松比达到最大值，约为0.343 Zr成分。

To develop new Ti alloys with low elastic modulus and high corrosion resistance, Ti-Zr binary alloys with Zr content of 0, 20, 40, 60, 70, 80, 100 at.% were prepared and their density, Young's modulus, Poisson's ratio and Vickers microhardness were investigated. Primary experimental results were as follows.1. DensityThe density vs. composition curve for the Ti-Zr binary alloys slightly deviated positively from the straight baseline connecting the two points on both ends for pure Ti and pure Zr. It is noted that the degree of deviation from the straight baseline was slightly greater in the Ti-rich region compared to the Zr-rich region.2. HardnessHardness of the as-cast pure Ti and Zr were 157 VHN and 196 VHN, respectively. The alloying addition of 20 at.% Zr to Ti drastically increased hardness, indicating that a great deal of solid solution hardening occurred. Further addition of Zr further increased Vickers hardness up to about 370 VHN at Ti-60 at.% Zr composition. Similar solid solution hardening was observed when Zr was alloyed with Ti. However, magnitude of increase in hardness was much weaker in the Zr-rich region compared to the Ti-rich region.3. Young's modulus and Poisson's ratioYoung's modulus of pure Ti was significantly higher than that of pure Zr. By alloying Ti with Zr, Young's modulus markedly decreased and the minimum Young's modulus of about 89 GPa was obtained at the Ti-60 at.% Zr composition. On the other hand, Poisson's ratio of pure Ti was significantly lower than that of pure Zr. By alloying Ti with Zr, Poisson's ratio markedly increased and the maximum Poisson's ratio of about 0.343 was obtained at the Ti-60 at.% Zr composition.