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The effect of alloy composition on improving glass-forming ability of La-based alloys is investigated in this work. Previous composition criteria demonstrated that the alloys with high glass-forming ability should have negative heats of mixing among the main constituent elements. In this study, the addition of Fe to a La-based La-Al-Ni-Cu alloy significantly improved the glass-forming ability, although the heat of mixing between Fe and the main element La is positive. La-Al-Ni-Cu-Fe bulk metallic glasses with diameters up to 15 mm were prepared by the method of pouring the molten alloys into a copper mold. These La-Al-Ni-Cu-Fe bulk metallic glasses exhibit relatively wide supercooled liquid region of about 50 k, and high T_rg(T_g/T_l) and γ(T_x/(T_g+T_l)) values. It is found that the addition of Fe to the La-Al-Ni-Cu alloy lowers the Gibbs free energy difference between the liquid and crystalline phases in the supercooled liquid region and enhances the glass-forming ability of the alloy.

Co(5 nm)/Dy(t${}_{\mathrm{\text{Dy}}}$)/Co(20 nm)/S and Ni(5 nm)/Dy(t${}_{\mathrm{\text{Dy}}}$)/Ni(20 nm)/S trilayer films are prepared by electron-beam sputtering to investigate the influence of dysprosium layer thickness (t${}_{\mathrm{\text{Dy}}}$) and thermal annealing on the crystal structure, magnetoresistance (MR) and magnetic properties of thin films. The thickness of Dy layer changed in the range from 1 nm to 20 nm. The samples annealed for 20 min at 700 K. Electron diffraction patterns reveal that the as-deposited and annealed systems Co/Dy/Co and Ni/Dy/Ni had fcc-Co + hcp-Dy and fcc-Ni + hcp-Dy phase state, respectively. It is also shown that at the t${}_{\mathrm{\text{Dy}}}$ = 15 nm the transition from amorphous to crystalline structures of Dy layer is observed. An increase in the Dy layer thickness results in changes in the MR and magnetic properties of the trilayer systems. It is shown that MR is most thermally stable against annealing to 700 K at t${}_{\mathrm{\text{Dy}}}$ = 15 nm for Co/Dy/Co as well as for Ni/Dy/Ni. For t${}_{\mathrm{\text{Dy}}}$ = 15 nm the, value of MR for both system increases by two times compared to those of pure ferromagnetic (FM) samples. The coercivity (B${}_c$), remanent (M${}_r$) and saturation (M${}_s$) magnetization of the in-plain magnetization hysteresis loops are related to the Dy layer thickness too. The coercivity depends on the FM materials type and diffusion processes at the layer boundary. Accordingly, M${}_r$ and M${}_s$ are reduced with t${}_{\mathrm{\text{Dy}}}$ increasing before and after annealing for both trilayer systems.