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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.

Nd₅₅Al₂₀Fe₂₅ bulk sample was prepared in the shape of rods 3 mm in diameter by suction casting. The sample exhibits typical amorphous characters in XRD pattern, distinct glass transition in DSC traces and hard magnetic properties. The distinct glass transition, which is invisible in DSC traces of previously reported Nd—Al—Fe ternary BMGs, allows us to investigate the glass forming ability (GFA) of Nd₅₅Al₂₀Fe₂₅ alloy using the reduced glass transition temperature T_rg and the recently defined parameter γ. However, it is found that the obtained diameter of the Nd₅₅Al₂₀Fe₂₅ glassy rod is much larger than the critical section thickness of the BMG predicted by either T_rg or γ. The microstructure of Nd₅₅Al₂₀ Fe₂₅ as-cast rod was studied and the apparent GFA of the alloy was supposed to be enhanced by the metastable nano-precipitates dispersed within the glassy matrix.

Recent work has shown that many metallic glass properties correlate with the Poisson ratio of the glass. We have developed a new model for simulating the atomistic behavior of liquids and glasses that allows us to change the Poisson ratio, while keeping the crystalline phase cohesive energy, lattice constant, and bulk modulus fixed. A number of liquid and glass properties are shown to be directly affected by the Poisson ratio. An increasing Poisson ratio stabilizes the liquid structure relative to the crystal phase, as indicated by a significantly lower melting temperature and by a lower enthalpy of the liquid phase. The liquids clearly exhibit two changes in behavior: one at low temperatures, associated with the conventional glass transition T_g, and a second, higher temperature change associated with the shear properties of the liquids. This second crossover has a characteristic, measurable change in the liquid structure.

Ti₄₀Cu₄₀Ni₁₀Zr_10-xSc_x (x = 0.5 and 1, at%) alloys were prepared by copper mould casting method. Microstructures of the ɸ 3 mm rod alloys were investigated by XRD and SEM. The results showed that the ɸ 3 mm rods were glassy matrix with TiCu crystalline phase. Mechanical properties were studied by compressive test. Ti₄₀Cu₄₀Ni₁₀Zr₉Sc₁ alloy exhibited good compressive strength over 2200 MPa and superior compressive deformation is about 7.9%.

In this study a nanometer-sized metallic glass (nano-MG) Ti₅₀Cu₅₀ was generated with constrained atoms at both ends and was extended until fracture under a tensile load by molecular dynamics simulation using the general embedded-atom model (GEAM) potential. Totally different mechanical behavior was observed in the nano-MG, such as strain hardening and necking, both of which have been discovered in a few real and simulated MGs and can be related to the generation of shear transformation zones (STZs). A dramatic drop in Young's modulus was found due to the surface effect. Such effect results from the large fraction of surface atoms which have a different surrounding configuration from bulk atoms. At fracture the nano-MG breaks by atomic separation as reported in metal nanowires. The fracture strain is as large as about 120%, indicating that nano-MGs are intrinsically ductile.

Zr-based amorphous alloys are promising materials applied in engineering field, due to their strong glass-forming ability, outstanding mechanical properties and relatively low cost. In this work, the crystallization kinetics of Zr${}_{56}$Co${}_{18-x}$Ni${}_x$Al${}_{16}$ ($x=0$, 2, 4 and 8; marked as Ni0, Ni2, Ni4 and Ni8, respectively) alloys are investigated in detail. The results show that, due to the addition of Ni, the glass transition of the alloys presents obvious dynamic characteristics, i.e., with the increasing heating rate, all characteristic temperatures are shifted to higher temperature. By fitting the Kissinger equation, the glass transition activation energy of Ni8 is the highest, indicating that Ni8 is much more difficult to crystallize. Therefore, the Ni8 alloy has the strongest anti-crystallization ability in the Zr${}_{56}$Co${}_{18-x}$Ni${}_x$Al${}_{16}$ alloys investigated.

The effect of compressive deformation on thermal stability and corrosive property of Zr${}_{61.7}$Al₈Ni${}_{13}$Cu${}_{17}$Sn${}_{0.3}$ bulk metallic glass with a strain of 80% was investigated in this work. The corresponding thermal stability is found to decrease after deformation and this can probably be attributed to the reduction of the viscosity and the increase of the Gibbs free energy after compressive deformation. In addition, the corrosion current density increases and this suggests that the corrosion resistance decreases for the deformed sample in comparison with the as-cast sample.

The effect of long-term room temperature ageing on structure and thermal stability of as-cast and inhomogeneously deformed Pd${}_{40}$Ni${}_{40}$P${}_{20}$ metallic glass has been investigated. It is found that the first crystallization peak temperature decreases and this indicates that the thermal stability decreases after ageing for these as-cast and inhomogeneously deformed metallic glass samples. The high density of shear bands formed after deformation disappears and nanocrystallization has been observed after ageing for the inhomogeneously deformed Pd${}_{40}$Ni${}_{40}$P${}_{20}$ metallic glass.

Theoretical computation of the pressure dependence of superconducting state parameters of binary Mg₇₀Zn₃₀ is reported using model potential formalism. Explicit expressions have been derived for the volume dependence of the electron–phonon coupling strength λ and the Coulomb pseudopotential μ* considering the variation of Fermi momentum k_F and Debye temperature θ_D with volume. The well-known Ashcroft's empty core (EMC) model pseudopotential and five different types of the local field correction functions viz. Hartree (H), Taylor (T), Ichimaru–Utsumi (IU), Farid et al. (F) and Sarkar et al. (S) have been used for obtaining pressure dependence of transition temperature T_C and the logarithmic volume derivative Φ of the effective interaction strength N₀V for metallic glass. It has been observed that the μ* curve shows a linear nature and an elbow is formed in the Φ graph.

The formation of nanocrystals in Zr-based alloys through three different routes, viz by rapid solidification of alloys, by crystallization of rapidly solidified metallic glasses and by crystallization of bulk metallic glasses has been described. The nanocrystal forming behaviors of rapidly solidified metallic glasses and bulk metallic glasses have been compared and contrasted. The rapidly solidified alloys, which have been examined for this purpose, are Zr₇₆Fe_24-xNi_x (x = 0,4,8,12,16,24) and Zr_69.5Cu₁₂Ni₁₁Al_7.5. In the Zr_69.5Cu₁₂Ni₁₁Al_7.5 alloy, formation of a quasicrystalline phase was observed on crystallization. Bulk glass having the composition Zr₅₂Ti₆Al₁₀Cu₁₈Ni₁₄ has been produced by copper mould casting. This has been crystallized in order to obtain nanocrystalline phases having Zr₂Ni and Zr₂Cu structures. The nanocrystalline and the nanoquasicrystalline microstructures have been examined in considerable detail in order to find out the nature of the various types of interfaces in them. Particularly the nanograin boundaries were examined by high-resolution transmission electron microscope (HREM) and their structure has been compared with that of the grain boundary in large grained material. The change in nature of these interfaces and their number with coarsening of the nanocrystal is also investigated.

Using combination of ferrofluid (FF) and Fe-based amorphous alloy in the advanced treatment of high concentration, organic wastewater was investigated. The addition of Fe_73.5Nb₃Cu₁Si_13.5B₉ amorphous alloy powders into a FF give rise to a dramatic enhancement in decreasing chemical oxygen demand (COD) and decolorization. The removal rate of COD by using FF that combined Fe_73.5Nb₃Cu₁Si_13.5B₉ metallic glass (MG) particles reached 92% in the presence of H₂O₂, nearly more than 50% higher than that by using only FF. Furthermore, compared with the FF, the decolorizing effect of the combination was 20% higher. It has been found that MG powders with the amorphous structures have high efficiency of waste water treatment and lead to high catalytic ability.

Metallic glasses have received considerable attention in comparison to normal metallic materials due to their superior physical, mechanical, electrical and magnetic properties. Understanding the glass transition kinetics of metallic alloys is of great importance in order to know its thermal stability. In the present paper, kinetics of glass transition of metallic glass Co₆₆Si₁₂B₁₆Fe₄Mo₂ is studied using thermal analysis technique, i.e. differential scanning calorimetry (DSC), by non-isothermal heating of the sample at four different heating rates. The activation energy (E) of the glass transition region is determined by two most frequently used methods, namely, Moynihan’s method and Kissinger’s equation. The fragility index, m is also calculated using T_g, which is a measure of glass forming ability of the given system. The results show that the fragility index ‘m’ of the given system falls below 16. This clearly indicates that the given system is strong liquid with excellent glass forming ability (GFA).

Laser powder bed fusion (L-PBF) is promising for producing metallic glasses (MGs) for its extremely high cooling rate and ability to manufacture complex geometrical components. However, the crystallization of MGs under different L-PBF parameters is not fully investigated, which has influences on the mechanical properties. In this study, we develop a multi-physics thermal-fluid flow model for the L-PBF process of MGs, run simulation cases for single tracks, and then analyze the molten pool morphology and crystallization behavior in the center and edge of the track, as well as the heat affected zone. The simulation results are validated against the experimental results in the literature and have provided deeper insight into the crystallization phenomenon observed in the experiments.

To extend the practical applications of the bulk metallic glasses (BMGs), the preparation of the metallic glass coatings on various substrates becomes an important research issue. Among the interfacial properties of the coatings, the adhesion between films and substrates is the most crucial. In this study, amorphous Zr₆₁Al_7.5Ni₁₀Cu_17.5Si₄ (ZrAlNiCuSi) thin films were deposited on SUS304 stainless steel at various sputtering powers by DC sputtering. According to the scratch tests, the introduction of the Cr and Ti buffer layers effectively improves the adhesion between the amorphous thin films and substrate without changing the surface properties, such as roughness and morphology. The antimicrobial results show that the biological activities of these microbes, except Acinetobacter baumannii, are effectively suppressed during the test period.