(1. 大连理工大学 三束材料改性教育部重点实验室&材料科学与工程学院，大连 116024；
2. 中国核动力研究设计院 反应堆燃料及材料重点实验室，成都 610213)
摘 要: 利用“团簇加连接原子”结构模型解析典型高温近α-Ti合金Ti 1100成分，进而在此基础上添加Hf、Ta和Nb元素进行合金化，形成成分通式 [Al-(Ti13.7(Zr/Hf)0.3)](Al0.69Sn0.18Si0.12(Mo/Ta/Nb)0.03)。合金组织结构分析和高温抗氧化性结果表明：Hf元素的添加并未改变合金的结构和组织，在此基础上，不同配比的Ta和Nb替代Mo时合金由片层转变β组织转变为等轴α组织；系列合金在800 ℃下，Hf替代Zr后合金的抗氧化能力显著提高，Ta和Nb进一步合金化后合金的抗氧化能力进一步增强，其100 h后的氧化质量增加约为(2.2±0.2) mg/cm2。
关键字: 近α-Ti合金；成分设计；微量合金化；高温氧化
（1. Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Ministry of Education,
School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China;
2. Science and Technology on Reactor Fuel and Materials Laboratory, Nuclear Power Institute of China,
Chengdu 610213, China）
Abstract:The composition characteristics of near α-Ti alloy Ti 1100 with the guidance of a cluster-plus-glue-atom model were investigated. A new alloy series with the cluster formula of [Al-(Ti13.7(Zr/Hf)0.3)](Al0.69Sn0.18Si0.12- (Mo/Ta/Nb)0.03) was designed by adding minor Hf, Ta, and Nb. The structures of alloys were characterized, and the oxidation resistance properties were measured. The results show that the Hf substitution for Zr doesn’t influence the β transition lamellar microstructure. While that various combinations of Ta and Nb to substitute for Mo could form equiaxed α microstructure. The oxidation-resistant capacities of designed alloys are enhanced obviously at 800 ℃ in comparison with that of Ti 1100. The oxidation mass gains of the designed alloys with Hf, Nb and Ta co-alloying after 100 h at 800 ℃ are about (2.2±0.2) mg/cm2.
Key words: near α-Ti alloys; composition design; minor alloying; high-temperature oxidation
