Behavior of Secondary Phase of As-cast V-5Cr-5Ti Alloy

作者：Li Zengde^*; Lin Chenguang; Cui Shun

来源：Rare Metal Materials and Engineering, 2017, 46(1): 104-110.

• vanadium alloy
• structure
• secondary phase
• lattice parameter

The as-cast microstructure of the V-5Cr-5Ti alloy was analyzed by XRD, OM, SEM and TEM. The behavior of second phase was investigated. The results show that the V-5Cr-5Ti alloy, fabricated by vacuum electron-beam melting, has coarse grains, which possess the characteristics of dendritic crystal made by lamellar secondary phase. The lattice parameters of metal vanadium and V-5Cr-5Ti alloy are 0.30316 and 0.30375 nm, respectively. The swelling of V cell volume is 0.58%. There are two kinds of secondary phase in the as-cast alloy, i.e. short strip secondary phase, which has fcc structure with the lattice parameter between 0.4182 similar to 0.4228 nm and elliptical-shaped secondary phase, which has fcc structure with the lattice parameter between 0.4186 similar to 0.4242 nm. In the process of solidification of the V-5Cr-5Ti alloy, Ti and C react to form metastable interstitial phase (Ti2C), which has fcc structure, or V and C react to form metastable interstitial phase (V2C), which has hcp structure. Then, atoms are substituted by each other. Finally, the secondary phases are formed, that is vanadium and chromium-alloyed precipitations of titanium oxycarbonitride, whose chemical formula is expressed as (Ti-2-CON).

• 出版日期2017-1
• 单位北京有色金属研究总院