As-Cast Microstructure Character of Vanadium Alloys Made by VAR

作者：Li Yufei^*; Luo Chao; Wang Zhigang; Huang Huogen; Jia Jianping; Tang Xian'e; Jiang Chunli

来源：Rare Metal Materials and Engineering, 2008, 37(12): 2152-2156.

• vanadium alloys
• chemistry composition
• cast state microstructure
• the second phase

Vanadium alloys was fabricated by VAR(vacuum arc remelting of consumable electrode) and its cast state microstructure was analyzed by XRD, OM, SEM and TEM. Results show that the impurities concentration of C, N, O is very high, and Ti and Cr both having melting loss at some degree. The real composition of ingot is V-3.7Cr-3.6Ti, There are a lot of pores in the ingot. There are three kinds of grain regions in the ingot obviously, and it's the typically solidification structure. The grain size in the chill regions is not uniform, and average grain size is about 500 pro. the grain sizes in the equiaxial region is also not uniform, while the average size is larger than chill region. The columnar region grain size is about 2 mm and the grains had been elongated obviously. The lattice parameter of the solid solution is 0.3021 nm. There are two kinds of the second phases in the alloy: 1) the precipitation, which is the Ti-rich type Ti-(CON), in the grains having the shape of "plate" with thickness up to 100 nm and the other two dimensions up to 1 similar to 2 mu m and forming the continuous films at grain boundaries; 2) the rare "globular" shape precipitation with 1 similar to 2 mu m in diameter, which also presumed to be the Ti-(CON).

• 出版日期2008-12
• 单位中国工程物理研究院