In response to the urgent demand for high-performance and cost-effective titanium alloys in the rail transit sector, this paper focuses on the recycling and utilization of TC4-DT titanium alloy returned scrap. A self-developed purification line is employed to process the turning scrap from ingot peeling. The purified scrap is blended with sponge titanium at a 30% ratio, followed by melting via a dual Electron Beam Cold Hearth Melting (EBCHM) and Vacuum Arc Remelting (VAR) process. Typical forgings are then prepared through open-die forging. To evaluate the removal capability of High-Density Inclusions (HDI) during EBCHM melting, a simulated test is designed. Results demonstrate that HDIs larger than 0.5 mm in diameter can be effectively captured by the cold hearth, while those smaller than 0.5 mm are dissolved under high temperature. High-precision industrial computed tomography is applied to conduct non-destructive inspection on three forgings. The results reveal a dense micro-structure, free from defects such as inclusions, pores, and cracks, confirming the reliability of the proposed purification and dual melting process.

Titanium alloy  /  Returned scrap  /  Electron beam cold hearth melting  /  High-density inclusion  /  Industrial computed tomography