Preparation of Low-Oxygen Ti–Si Alloys by Electromagnetic Separation

Titanium–silicon (Ti–Si) alloys are widely used in aerospace, automotive manufacturing, and medical devices. A promising method to prepare these alloys involves utilizing solid wastes containing Ti and Si. However, resultant alloys often contain numerous slag particles (oxide inclusions), significantly hindering their broader application. To address this challenge, this study introduced electromagnetic separation as a novel method to remove oxygen (O) impurities from Ti–Si alloys. First, the study investigated the reasons for oxide inclusions in the alloys. Second, it explored the effects of temperature, time, and alloy composition on the preparation of low-O Ti–Si alloys. The results indicated that the residual oxide inclusions in Ti–Si alloys were primarily due to the high viscosity of the alloys while increasing Ti content in the alloy decreased the removal of O impurities. Additionally, the study investigated the influence of melt viscosity and conductivity on the electromagnetic separation of O impurities. The results indicated that with increasing Ti content in the alloy, both conductivity and viscosity increased, thereby impairing O impurity separation. Maxwell’s equation and \({\text{k - }}\varepsilon\) $\text{k -}\epsilon$ turbulent flow models were developed at a current of 29.1 A and a frequency of 3.72 kHz, with simulations conducted using COMSOL Multiphysics 6.1 software. These simulations indicated that the efficiency of electromagnetic separation was primarily affected by conductivity when Ti content ranged from 23.2 to 31.5 wt pct, while viscosity became the dominant factor when the Ti content was between 41.7 and 55.9 wt pct. This study offered valuable experimental insights into the preparation of low-O Ti–Si alloys using electromagnetic separation.