Affiliation of Author(s):能源与动力学院
Journal:RARE METAL MATERIALS AND ENGINEERING
Key Words:molecular dynamics TC4 ternary alloy radial distribution function phase change diffusion coefficient
Abstract:The aging phase transition and diffusion bonding of TC4 was studied by a molecular dynamics method. The radial distribution function of TC4 ternary alloy and the relative content of different crystal structures were analyzed. At the same time, the atomic concentration distribution, diffusion connection width and diffusion coefficient of diffusion bonding process at different thermal insulation temperatures were studied. The results show that the structural changes of TC4 in the aging phase transition are mainly manifested by the precipitation of new a phase from the metastable beta phase, and the beta phase content reaches 23% after the state stabilizes, which is in good agreement with the experimental results. In the process of TC4 diffusion bonding, the titanium atoms near the interface dominate the diffusion, and the vanadium atom diffusion is the secondary, while the aluminum atoms are relatively few. Under the same conditions, the diffusion connection width and the thermal insulation temperature are in a good linear relationship. The diffusion coefficient of titanium is exponentially related to the temperature of heat preservation, and the results are in accordance with the experiment.
ISSN No.:1002-185X
Translation or Not:no
Date of Publication:2018-10-01
Co-author:wcs,Li Baiyang,ghd
Correspondence Author:lxg