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The lack of ductility is known to be one of the major drawbacks of amorphous state. Recently, an increase in the tensile strength and ductility was found in the ${\text{Ni}}_{82.1}$${\text{Cr}}_{7.8}$${\text{Si}}_{4.6}$${\text{Fe}}_{3.1}$${\text{Mn}}_{0.2}$${\text{Al}}_{0.1}$${\text{Cu}}_{0.1}$B₂ metal glass ribbon pre-annealed at $\beta$-relaxation temperature. This paper analyzes the surface relief transformation observed during this process and the nature of separate inhomogeneities. The most significant effect is a flattening of the surface relief. This case was confirmed by statistical processing. Thus, the surface relief change was shown to be a clear indicator of structure relaxation process, that occurs in a metal glass ribbon well below its crystallization.

Effects of test temperature and alloy composition on dynamic deformation behavior of Zr-based amorphous alloys were investigated in this study. Dynamic compressive tests were conducted in the temperature range from room temperature to 380°C using a compressive Kolsky bar. Dynamic compressive test results indicated that both maximum compressive stress and total strain of the amorphous alloys decreased with increasing test temperature because shear bands could propagate rapidly as the adiabatic heating effect was added at high temperatures. Maximum compressive stress and total strain of the alloy containing ductile β crystalline phases were higher than those of the monolithic amorphous alloys over the tested temperature range because β phases played a role in forming multiple shear bands. The alloys having lower T_g or ductile phases had more excellent dynamic properties than the LM1 alloy.

The crystallization of melt-spun Fe-Pt-B amorphous alloy with a thickness of 20 µm in steady high magnetic field (HMF) was investigated. The intensity of the applied magnetic field is 0-10 T along with the ribbons annealed at temperature ranging from 673 K to 873 K. The direction of the performed magnetic field is perpendicular to the direction of surface velocity of the Cu wheel. The thermal magnetic properties of the samples were obtained by the thermal gravity analyzer with a magnet attached to the outside of the furnace filled with flowing inert gas. The phase transformations of Fe-Pt-B amorphous alloy on heating with and without the steady HMF were studied by X-ray diffractometry together with the melt-spun ribbon. The average grain size of the samples annealed in HMF was about 10 nm calculated from the XRD patterns. The HMF was thought to be effective on the refinement of nanograins which were produced by the crystallization of the amorphous ribbon during the annealing process.

The glass-forming ability (GFA) and magnetic properties of the minor Zr-substituted Gd${}_{50}$Co${}_{50}$ amorphous alloy were investigated. The Gd${}_{50}$Co${}_{48}$Zr₂ amorphous ribbons prepared by melt-spinning show better GFA. With increasing minor Zr addition, the Gd${}_{50}$Co${}_{48}$Zr₂ amorphous ribbons possessed higher magnetic entropy change peak ($-\mathrm{\Delta }$S${}_m^{\mathrm{\text{peak}}}$ = 3.9 Jkg${}^{-1}$K${}^{-1}$, under 5 T) but lower Curie temperature (T${}_c$ = 231 K) than the Gd${}_{50}$Co${}_{50}$ amorphous alloy. The mechanism for the improved GFA, magnetocaloric effect (MCE) and the decrease in T${}_c$ was investigated. Finally, combined with other Gd-based amorphous ribbons, the Gd${}_{50}$Co${}_{48}$Zr₂ amorphous alloy was employed to construct amorphous composites to achieve a table-like magnetic entropy change profile, which can provide optimal efficiency when utilizing an Ericsson thermodynamic cycle.

A Ni–Fe–B–Si–Nb amorphous alloy was deposited on a steel substrate surface via a laser cladding process, and a laser cladding plus laser remelting process. The wear behavior of the laser processed samples and the bulk metallic glass (BMG) sample with the same nominal composition were tested using a pin-on-disc type testing machine. The nano-mechanical properties of the samples were measured with a nano-characterization system. The friction wear tests showed that deep grooves and wear debris were formed on the worn surface of the laser cladded coating, while only shallow grooves for the laser remelted coatings. The friction coefficients of laser remelted coatings and BMG were lower than the laser cladded coating. The wear mass losses of the laser remelted coating were less than the BMG when the laser remelting scanning speed was higher than 6 mm/min. The nano-hardness and elastic modulus of the remelted coating is higher than that of the laser cladded coating. Also, they increase with the increasing laser scanning speed with 1227.9 HV and 277.4 GPa when the remelting scanning speed is 8 m/min. Based on the nano-indentation and friction wear tests results, it was found that the friction wear properties of the laser cladded coating, laser remelted coatings and BMG related well to the ratio of H³/E². A higher value of H³/E² can lead to a better wear resistance property.

Microstructure of Fe-based amorphous and nanocrystalline soft magnetic alloy has been investigated by X-ray diffraction (XRD), transmission electronic microscopy (TEM) and Doppler broadening positron annihilation technique (PAT). Doppler broadening measurement reveals that amorphous alloys (Finemet, Type I) which can form a nanocrystalline phase have more defects (free volume) than alloys (Metglas, Type II) which cannot form this microstructure. XRD and TEM characterization indicates that the nanocrystallization of amorphous Finemet alloy occurs at 460°C, where nanocrystallites of α-Fe with an average grain size of a few nanometers are formed in an amorphous matrix. With increasing annealing temperature up to 500°C, the average grain size increases up to around 12 nm. During the annealing of Finemet alloy, it has been demonstrated that positron annihilates in quenched-in defect, crystalline nanophase and amorphous-nanocrystalline interfaces. The change of line shape parameter S with annealing temperature in Finemet alloy is mainly due to the structural relaxation, the pre-nucleation of Cu nucleus and the nanocrystallization of α-Fe(Si) phase during annealing. This study throws new insights into positron behavior in the nanocrystallization of metallic glasses, especially in the presence of single or multiple nanophases embedded in the amorphous matrix.

Small amount of Ni was added in the ${\mathrm{\text{Gd}}}_{50}{\mathrm{\text{Co}}}_{50}$ binary alloy to replace the Co element for improving the formability and magnetic properties of the binary amorphous alloy. It was found that the glass formability of the ${\mathrm{\text{Gd}}}_{50}{\mathrm{\text{Co}}}_{50}$ amorphous alloy was significantly improved by Ni addition. The Curie temperature $(T_c)$ of the ${\mathrm{\text{Gd}}}_{50}{\mathrm{\text{Co}}}_{50-x}{\mathrm{\text{Ni}}}_x$ metallic glasses decreases with the Ni addition, and the maximum magnetic entropy change $(-\mathrm{\Delta }{S}_m^{\mathrm{\text{peak}}})$ was also improved. The mechanism for the effect of adding a small quantity of Ni on the $T_c$ and $-\mathrm{\Delta }{S}_m^{\mathrm{\text{peak}}}$ of the ${\mathrm{\text{Gd}}}_{50}{\mathrm{\text{Co}}}_{50}$ amorphous alloy was studied.

Fe-Zr-B-based amorphous alloys (AAs) show good magnetocaloric effect (MCE) around the ambient temperature, and their maximum magnetic entropy change ($-\mathrm{\Delta }{S}_m^{\mathrm{\text{peak}}})$ generally increases with their Curie temperature ($T_c)$, which means the poor magnetocaloric properties near the cold end of the air conditioner. In this work, by adding 2% (at.%) Ti to replace the Zr element in a ${\mathrm{\text{Fe}}}_{88}{\mathrm{\text{Zr}}}_8{\mathrm{\text{B}}}_4$ AA, we successfully fabricated the ${\mathrm{\text{Fe}}}_{88}{\mathrm{\text{Zr}}}_6{\mathrm{\text{B}}}_4{\mathrm{\text{Ti}}}_2$ amorphous ribbon. The ${\mathrm{\text{Fe}}}_{88}{\mathrm{\text{Zr}}}_6{\mathrm{\text{B}}}_4{\mathrm{\text{Ti}}}_2$ amorphous ribbon exhibits a slightly enhanced glass formability, improved $-\mathrm{\Delta }{S}_m^{\mathrm{\text{peak}}}$ and decreased $T_c$ when compared to the ${\mathrm{\text{Fe}}}_{88}{\mathrm{\text{Zr}}}_8{\mathrm{\text{B}}}_4$ AA. The results are helpful for developing better MCE of the Fe-Zr-B-based metallic glasses working near the cold end of a domestic magnetic air conditioner.

In this study, a new evaluation method was investigated for the magnetic properties of the amorphous alloys by comparing the experimental results with the theoretical calculations. First, The (Fe${}_{70}$Co₆P${}_{4.8}$Si${}_{9.6}$B${}_{9.6}$)${}_{100-x}$Cu_x ($x=0$–0.5) amorphous ribbons were prepared by melt spinning method. Then, the magnetic properties of the prepared amorphous alloys were measured as 165.86–147.04emu/g, respectively. On the other side, we analyzed the valence electron structure and obtained the magnetizations as 159.92–158.77emu/g by calculating the magnetic moments of unit cells based on empirical electron theory (EET) of solids and molecules. Through comparing the magnetic properties of the calculations with the measurements, we found that the differences between the calculations and the measurements are less than 12% for all samples, meeting the first approximation requirement. Moreover, with the addition of Cu, the change trends both in the calculated and measured magnetic properties are also consistent. These results prove that it is feasible to calculate the magnetic property of the amorphous alloy from the valence electron level using EET, which provides a new method to investigate the soft magnetic property of the amorphous alloy instead of the real measurement.

Generation of hydrogen by sodium borohydride solution had attracted lots of attention. A serial of nanosized NiB catalysts were prepared using the chemical reduction method through introducing AlCl₃ into the preparation. Catalytic performance of NiB catalysts were investigated in the hydrolysis of alkaline NaBH₄ solution. The catalysts were characterized by X-ray diffraction (XRD), N₂ adsorption, Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The results showed that NiB catalysts possessed amorphous alloy structure, and the particle size could be adjusted by the AlCl₃ amount. Catalytic performance showed that NiB catalyst with smaller particle size had much higher activity. The NiB catalyst also displayed high stability, the catalytic activity could retain about 84% of its initial value after four cycles.

Amorphous Ti₅₀Ni_(50-x)Cu_x (at.%) (x = 15, 20 and 25) alloy ribbons were prepared by melt spinning, and then their crystallization behavior was investigated by optical microscopy, transmission electron microscopy, X-ray diffraction and differential scanning calorimetry. Wavenumber (Qp) decreased from 29.40 nm^-1 to 29.29 nm^-1 and ΔT(T_g - T_x) increased from 31 K to 36 K with increasing Cu content from 15 at.% to 25 at.%, suggesting that glass forming ability of Ti–Ni–Cu alloy ribbons increased with increasing Cu content. Activation energy for crystallization decreased from 211.5 kJ/mol to 136.4 kJ/mol with increasing Cu content from 15 at.% to 25 at.%, suggesting that a stability of Ti–Ni–Cu amorphous decreased with increasing Cu content.