Possibility of As-cast Applications on beta-type Titanium Alloys for Energy-saving Measures

摘要

Many complex post processing treatments have been applied after casting to production of conventional (3-type Ti alloys with high strength and toughness, which led to their highly final costs. The high performance alloys with the ultimate tensile strength (σ _(UTS)) of 1000 MPa and fracture strain (ε_f/) of 10% just at as cast condition leads to a landmark alloy-development for energy-saving measures, compared with conventional alloys such as TUT 1A (Ti-13V-3Al-3Cr-2Nb) and 15-3-3-3 (Ti-15V-3Cr-3Sn-3Al) with high performance produced by complex post processing. In this study, the new compositions of β type Ti alloys for as cast applications were proposed in the region greatly differ from conventional alloys, in the bond order (Bo) and d-orbital energy level (Md) diagrams showing the phase boundaries of β, β+α and a phases, as shown in Fig. The proposed alloy ingots were produced by the cold crucible levitation melting (CCLM) technique as the single manufacturing process in saving energy, their microstructures were controlled by adjusting its process parameters.