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The effect of alloying on the formation enthalpy of TiCu intermetallics was investigated via first-principles calculations to propose a new design method for Ti–Cu-system metallic glasses. The calculation results showed good agreement with the reported experimental results that Ni, Pd, Sn and Zr improve this system’s glass-forming ability. According to the calculation results, a Ti–Zr–Cu–Ga system was designed as a potential new bulk Ti-based metallic glass, and a bulk sample with a 2-mm diameter was fabricated.

Parameters for evaluating the glass-forming ability (GFA) in Ti–Cu system metallic glasses were considered by investigating the effect of additional elements (Fe, Co, Ni, Si, Zr, Cr) on structural changes and onset temperatures associated with each exothermic peak on heating. The differential scanning calorimetry curves of Ti–Cu system metallic glasses (added Ni, Cr, Zr) exhibited two exothermic peaks. Moreover, the sample containing Zr maintained its halo peak when the sample was annealed at first exothermic peak. The results indicate that the onset temperature of the second exothermic peak ( T x 2 ) is an important temperature reflecting the resistance of the supercooled liquid to crystallization. The GFA of Ti–Cu system metallic glasses are expressed well by parameters containing T x 2 .

New Ti-based metallic glasses were designed and fabricated in the ternary component alloy system Ti–Zr–Co. The constituent elements of the alloy system were selected based on three empirical rules proposed by Inoue, Turnbull, Senkov and Miracle, and by a new parameter called the effective atomic radius, which is based on the first-principles calculations for 2.78 at.% hcp Ti alloys. The reported scheme based on the concept of binary eutectic clusters was applied to predict the alloy composition that shows a glass transition, Ti44Zr30Co26. We prepared Ti44Zr30 + xCo26 − x, Ti46Zr28 + xCo26 − x, and Ti48Zr26 + xCo26 − x (x = 0, 4, 6, 8) alloy sheets using a single roller method. The new Ti-based ternary metallic glasses exhibited vitrification for many compositions around the predicted composition of Ti44Zr30Co26. The greatest value of the super-cooled region ⊿Tx was 34 K for Ti48Zr32Co20.

New Ti-based ternary metallic glasses were designed and fabricated. A new parameter called effective atomic radius in the Ti solid solution from ab-initio calculation was used to design of the Ti-based metallic glasses. From the effective atomic radius, Ti-Zr-Mn, Ti-Zr-Fe and Ti-Zr-Co systems can be considered as a new Ti-based ternary metallic glass. And the reported scheme based on the concept of binary eutectic clusters is applied to predict alloy composition which shows glass transition.We prepared the Ti42Zr22Mn36, Ti43Zr29Fe28 and Ti44Zr30Co26 alloy sheets by a single-roller method. It showed that sharp diffraction peak corresponding to crystalline phases could be observed in the XRD spectra of Ti42Zr22Mn36 and Ti43Zr29Fe28. While for alloy with Ti44Zr30Co26 no sharp diffraction peak could be found except broad diffraction halos. This result suggests that a critical eutectic temperature in the phase equilibrium for forming glass phase is around 1000°C.