Microstructure and Mechanical Properties of Vacuum Centrifugal Casted Ti-6Al-4V Alloy by Casting and Heat Treatment

The Ti-6Al-4V alloy has been widely used for structural materials due to high specific strength property, however it is difficult cast because of reactivity at temperature. In this study casting characteristics and post-casting heat treatment were studied in the Ti alloy. was prepared using high-frequency induction heating horizontal vacuum centrifugal reduce reaction with crucible mold by minimizing overheating molten metal fast. thin a thickness 2 mm, α’ martensite observed, 4~8 α+β Widmanstätten observed. As increased, grain size, α-lath width, α-case increased. Accordingly, as hardness matrix decreased surface addition, when treated below β-phase transformation temperature, width quenched after temperature region, an formed. On other hand, atmosphere, confirmed that elongation very low hydrogen oxygen atmosphere induced. addition defects can be removed through HIP.