Numerical Study on the Solid-Liquid Interface Evolution of Large-Scale Titanium Alloy Ingots During High Energy Consumption Electron Beam Cold Hearth Melting

摘要

In the present paper, a three-dimensional thermal-fluid multi-physical model has been established to investigate the effect of energy consumption operations on the evolutionary tendency of the solid-liquid interface for large-scale Ti-6 wt.%Al-4 wt.%V (TC4) round (phi 260 mm and phi 620 mm)/slab (1050 mm x 220 mm) ingots produced by electron beam cold hearth melting. The results qualitatively revealed the evolutionary tendency of the solid-liquid interface in different casting conditions, indicating that the solid-liquid interface with a gentle casting speed at a low pouring temperature will generate symmetric solid-liquid interfaces which were slightly affected by the modification of the pouring temperature. With an increasing energy input resulting from the rising casting speed, the deformation of the solid-liquid interface near the inlet was increased. As a result, the risk of breaking out and the formation of a non-uniform microstructure in the phi 620-mm round ingots and slab ingots was greatly increased.