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U-Fe-based ternary alloys have showed weaker glass forming ability (GFA) than U-Co-based ones, although U-Fe is a better base glass system than U-Co. To solve this puzzling point, the present work was aimed to study the formation of U-Fe-Al metallic glasses (MGs) together with their crystallization and corrosive properties. Through melt-spinning, the U-Fe-Al alloys designed by introducing Al to U-Fe alloys in the eutectic zone formed fully glassy phase in a large composition range. Among them, U60Fe27.5Al12.5 is the best glass former having the maximum Tg, Tg/Tm and supercooled liquid region of 635 K, 0.612 and 48 K, respectively. Its GFA exceeds other known U-based MGs including the U-Co-based ones. Moreover, compared with some U-Co-based MGs and crystalline uranium materials, U60Fe27.5Al12.5 MG also displayed more excellent anti-corrosive performance in neutral solution, indicating alluring application prospect in nuclear-related fields. However, these U-Fe-Al MGs exhibited very low Tg/TL values, which is essentially owing to that their compositions may be hypoeutectic and lie on the side of the Fe2U-typed eutectic phase with melting point much higher than the eutectic temperature.

The alloying effects of the like-atom substitution of Ni and Co for Fe on the various properties of Fe70B16.7Si8.3Ta5 metallic glass are investigated in this present work. New Fe-based bulk glassy alloys, namely Fe60–x Co x Ni10B16.7Si8.3Ta5 (at.%; x = 10, 20 and 30) with critical diameters up to 1.5 mm, were made by means of copper mold casting. A new glass-forming ability indicator, viz., the enthalpy of supercooled liquid, has been introduced for assessment of the glass-forming abilities (GFAs) of these Fe-based multi-component alloys. Nano-indentation results indicate that the calculated elastic modulus and hardness of the bulk glassy alloys are lower than those of the Fe70B16.7Si8.3Ta5 alloy. Among these bulk glassy alloys, Fe70B16.7Si8.3Ta5 exhibits the large elastic modulus and hardness with values of 178 ± 1 GPa and 12.9 ± 0.1 GPa, respectively. All the bulk glassy alloys exhibit good soft magnetic properties with high saturation magnetization B s ~ 0.75–1.04 T but low coercive force H c ~ 0.2–5.2 A/m.

Ni-Hf binary alloys are merely known as a category of marginal glass formers. In this system, the assessment of glass-forming abilities has not been made and the optimal glass-forming composition remains unclear. In the present work, Ni-Hf glass-forming compositions are explored using the atomic cluster plus glue atom model. Ni-Hf phase diagram shows a deep eutectic point at Ni65Hf35 which is associated two intermetallic phases, namely, Ni7Hf3 and Ni10Hf7. A predominant atomic cluster was first derived from the crystalline structures of the deep eutectic related phases, and several glass-forming compositions were determined considering the one or three glue atoms constraint condition. Rapid quenching results show that Ni71.43Hf28.57 and Ni68.75Hf31.25 metallic glasses can be made fully glassy. The latter can be well described with the model composition formula as [Ni-Ni7Hf5]Ni3. Among the melt-spun alloys, the Ni68.75Hf31.25 glass which locates in between the deep eutectic point and the Ni7Hf3 phase in the phase diagram, exhibited a highest crystallization temperature of 877 K and a lowest liquidus of 1482 K, and hence is suggested to be the optimal Ni-Hf glass former by the high reduced glass temperature criterion.

Minor Fe additions are widely added to enhance the corrosion resistance of cupronickel alloys. The present paper aims at optimizing the amounts of Fe in Cu 70 (Ni,Fe) 30 (at.%) alloys using a cluster-plus-glue-atom model for stable solid solutions. By this model, it is assumed that one Fe atom and 12 Ni atoms formed a Fe-centered and Ni-surrounded cube-octahedron cluster and the isolated FeNi 12 clusters embedded in a Cu matrix. The stable solid solution alloy composition of Fe-modified Cu 70 Ni 30 alloy was described by a cluster formula [Fe 1 Ni 12 ]Cu 30.3 = Cu 70 Ni 27.7 Fe 2.3 (at.%). The effect of homogenizing annealing treatment on the microstructure and corrosion resistance was also investigated by XRD, TEM and electrochemical corrosion measurements. The corrosion test indicates that the Cu 70 Ni 27.7 Fe 2.3 alloy annealed at 800 °C for 5 h possesses the best corrosion resistance in 3.5% NaCl solution.

ZrN thin films were prepared on 45# steel by using ECR-microwave plasma source enhanced dc magnetron sputtering. The increase of the N2 partial pressure PN2 leads to phase transitions from ZrN and an orthorhombic ZrNx phase to an amorphous phase. At PN2 = 1.1×10−2Pa to 4.5×10−2Pa, the films contain both ZrN and ZrNx (a = 0.3585, b = 0.4443, c = 0.5798 nm). At PN2 = 5.0×10−2 Pa, the film shows a strong tendency towards the amorphous phase. The N concentration at different PN2 varies from 7.73 to 66.96% according to electron probe analysis. The microhardness of the samples, varying from 19.82 GPa to 26.73 GPa, first increases and then decreases with increasing PN2. The hardest sample has a wear rate of about 4.5×10−5 mg/min. The property changes are relative to the film structure due to different N2 partial pressures.

Uranium-based amorphous alloys are a unique family of amorphous materials, which have so far been less studied due to the high chemical activity and radioactivity of uranium metal. In this paper, we review the compositions, preparations and thermal stability characteristics of U-based amorphous alloys obtained in the early experimental studies, and summarizes our recent results of the preparations and material properties of stable U-based amorphous alloys. The latest progress in our study of U-based amorphous alloys is presented in the three aspects. Firstly, the preparation methods, alloy systems and compositions, formation and crystallization behaviors of the new U-based amorphous alloys, along with the preliminary mechanisms for their formation and structure stabilization are reviewed. A number of new uranium-based amorphous alloy systems have been established based on eutectic law and structural packing model. These alloys show high ability to form glass, and the reduction of glass transition temperatures of some alloys to those of conventional amorphous alloys. The formation rules of binary (U-Fe/U-Co/U-Cr), ternary (U-Co-Al/U-Fe-Sn) and multicomponent alloy system have been investigated. It was found that the ability to form glass is strongly related to some physical parameters such as the local cluster structure, the electron concentration, the enthalpy of mixing, the electronegativity of the alloy component as well as the atomic size. The fragilities of U-based amorphous alloys indicate that they belong to a class of strong glass forming system, which means that the critical dimensions of such amorphous alloys can be further enhanced, and bulk amorphous samples are expected to be prepared. The crystallization activation of this kind of amorphous alloy is higher, and the crystallization process is dominated by nucleation. Then, the microstructures especially the first high-resolution electron microscopic results of the unique amorphous materials are reviewed. Finally, the micro-mechanical and anti-corrosion properties are reported in great detail. It is found that U-based amorphous materials show excellent mechanical properties and corrosion resistance, and the strength and hardness are much higher than those of conventional crystalline uranium alloys, and the corrosion resistance is also superior to the latter, which may be caused by its disorderly amorphous structural characteristics. Amorphous alloys have been the subject of intense fundamental and application research in recent years. Stable U-based amorphous alloys appear to cover all physical phenomena displayed by amorphous alloys. The discovery of outstanding properties in these new alloys therefore would stimulate both the fundamental studies including structure, electronic, glass transition, crystallization, etc., and the application-orientated studies of the thermal stability, mechanical and corrosion properties.

We report the preparation of cerium activated lithium glass scintillators for thermal neutron detection and their properties. The technological requirements and appropriate compositions are proposed, by which high detection efficiency of lithium glass scintillators for thermal neutrons can be obtained. When used as neutron detectors, the 6Li glass ST-602 affords excellent pulse height discrimination against gamma radiation, particularly in the case of thin 6Li glass.