论文名称：The alloying elements dispersion and its mechanisms in a Ni-based superalloy during electron beam remelting
论文类型：期刊论文
发表刊物：VACUUM
收录刊物：SCIE、EI
卷号：166
页面范围：107-113
ISSN号：0042-207X
关键字：Ni-based superalloy; Elements dispersion; The marangoni effect; Diffusion; Electron beam remelting
摘要：The dispersion of alloying elements in superalloy during Electron Beam Technology (EBT) is an important and unreported issue. In order to investigate this problem, dispersion of alloying elements and the corresponding influence on y phase and hardness are investigated for K417 Ni-based superalloy remelted by EBT in which the vacuum is kept at 2-5 x 10(-2) Pa. Cr, Ti and Mo segregate obvious after remelting. Especially for Cr, its concentration increases to 8.200 wt% in upper layer of melt alloy after melting procedure and ultimately decreases to 6.740 wt%; the concentration in lower part ultimately increases to 8.599 wt%, which is much higher than origin concentration of 7.906 wt%.The increase of Cr in lower part gives rise to strength of gamma phase, therefore increasing micro-hardness. Sharp temperature gradient in the melt and the Marangoni effect dominate the dispersion of alloying elements before the temperature of melt reaching ebullition point. Ebullition of the melt completely counteracts the Marangoni effect and move elements gathered by temperature gradient to the bottom of melt. The results of the investigation will help guide the application of electron beam technology on Cr contained superalloy for the dispersion mechanisms.
发表时间：2019-08-01