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The crystallization of the Zr62Al8Ni13Cu17 bulk amorphous alloy upon isothermal annealing was significantly retarded under high magnetic fields. The intensity of the magnetic field and permeability difference between the amorphous phase and the precipitates are proposed as the key factors involved in stabilizing the amorphous phase under high magnetic fields.

The icosahedral phase formation and associated structural evolutions in the Al–Cu–Fe ternary system have been examined through the repeated cold rolling and folding (R&F) process of elemental foils with a target composition of Al 62.5 Cu 25 Fe 12.5 (at.%). Upon early increments of the rolling and folding cycles, the elemental Fe foil was dispersed through the refined Al and Cu layers. When the rolling and folding step reached 40 cycles the Al 2 Cu phase has been observed, however, no ternary phases were identified even upon additional R&F cycles. The stable icosahedral phase (i-phase) could be obtained after isothermal annealing of the R&F processed specimens at 650 and 750 °C. The phase evolution during repeated cold R&F process of the Al–Cu–Fe system and upon heat-treatments are discussed in terms of the formation and dissolution of the Al 2 Cu and Al 7 Cu 2 Fe phases.

The effect of Sn substitution for Si on the glass forming ability (GFA) and crystallization behavior has been studied in Ni59Zr20Ti16Si5 − xSnx (x=0, 3, 5) alloys. A bulk amorphous Ni59Zr20Ti16Si2Sn3 alloy with diameter up to 3 mm can be fabricated by injection casting. Partial substitution of Si by Sn in Ni59Zr20Ti6Si5 − xSnx alloys improves the glass forming ability. The improved GFA of the Ni59Zr20Ti16Si2Sn3 alloy is can be explained based on the lowering of liquidus temperature. The crystallization sequence becomes completely different with addition of Sn. The amorphous Ni59Zr20Ti16Si5 alloy crystallizes via precipitation of only a cubic NiTi phase in the first crystallization step, whereas the amorphous Ni59Zr20Ti16Si2Sn3 alloy crystallizes via simultaneous precipitation of orthorhombic Ni10(Zr,Ti)7 and cubic NiTi phases. Addition of Sn in the Ni59Zr20Ti16Si5 alloy suppresses the formation of the primary cubic NiTi phase. The bulk amorphous Ni59Zr20Ti16Si2Sn3 alloy exhibits high compressive fracture strength of about 2.7 GPa with a plastic strain of about 2%.

Ni-based metallic glasses containing no metalloids are developed in Ni–Zr–Nb–Al alloy system. A partial replacement of Zr with Nb in Ni–Zr–Al alloys significantly enhances the glass-forming ability (GFA) and enlarges the undercooled liquid region during continuous heating of glassy ribbons. A quaternary Ni–Zr–Nb–Al metallic glasses exhibit large undercooled liquid region (>50 K), indicating high glass-forming ability of the alloy. The glass transition and crystallization temperatures of a quaternary Ni61Zr28Nb7Al4 alloy are 848 and 898 K, respectively, exhibiting a wide undercooled liquid region of 50 K. A complete Ni61Zr28Nb7Al4 glassy rod (φ1 mm) can be prepared by copper mold injection casting.

Quaternary Ni-based amorphous alloys containing only metallic elements were developed through systematic alloy design. The importance of the phase equilibria information for the development of amorphous alloys was demonstrated through experimental results. Ni−Zr−Al ternary alloys having low liquidus temperature tend to have high GFA. Partial replacements of Zr with Y in the ternary alloys significantly enhanced the GFA of the quaternary alloys. The alloy Ni60Zr25Al8Y7 could be cast into a fully amorphous rod through an injection casting method. Since most Ni-based amorphous alloys reported to date contain non-metallic elements, the Ni-based amorphous alloys developed in the alloy system Ni−Zr−Al−Y are of interest.

For the high pulverized-coal ratio (PCR) operation in the blast furnace, the slag volume should be minimized to secure good gas/ liquid permeability in the low part of the blast furnace. As a measure of slag volume reduction, the MgO content in the sinter has been reduced to the level of 5%. As the slag volume is reduced, the chemistry of slags formed is expected to be changed. Using the tuyere probing technique in the field trials, the effects of slag volume reduction on the slag chemistry was studied. Based upon the analysis of the field trial data as well as laboratory experiment results, it is elucidated that the enhanced gas/liquid permeability is attributed not only to the slag volume reduction but also to the decrease of bosh slag viscosity. By lowering MgO content in the sinter, the bosh slag viscosity can be effectively decreased leading to a stable high PCR/low slag volume operation of the blast furnace.

Composites consisting of icosahedral (i) phase and ductile α-Mg can be fabricated by controlling the alloy composition. With increasing Mg content, the primary solidification phase changed from the i phase to the α-Mg phase and single eutectic structure can be obtained at a composition of Mg72Zn23.5Y3.5. The i phase showed a variation in structural order from the well-ordered icosahedral phase to the 1/1 rhombohedra1 approximant with lattice constants a=27.2 A and α = 63.43°. The structural change in the i phase can be explained by microdomain formation due to compositional change during solidification. Annealing treatment improves the structural order of the i phase by homogenization. By controlling the alloy composition, a single eutectic structure consisting of a hard i phase and a ductile α-Mg phase could be obtained.

Microstructural investigations on ultrafine eutectic (Ti 65 Fe 35 ) 100− x Sn x alloys with x = 0, 1 and 3 at.% reveal that additional Sn is effective to control formation of the micron-scale dendrites and to decrease the length-scale of lamellar spacing with enhancing macroscopic plasticity at room temperature compression. Hence, it is possible to understand the influence of the microstructural change on the plasticity of the ultrafine eutectic Ti–Fe–Sn alloys.

Bulk metallic glasses have a frozen-liquid structure comprising multi-component elements. Plastic deformation of bulk metallic glasses is highly localized into shear bands. As the shear band propagates, excess free volume is generated and spontaneously coalesced, leading to the formation of nanometer-scale voids. The voids evolve to be cracks that immediately cross the whole sample area causing a catastrophic fracture even under compression. Therefore, to prohibit the catastrophic failure, atomic clustering kinetics should be retarded. Here, we report a new monolithic zirconium-base metallic glass that is highly deformable without global failure under compression. Due to high thermal activation energy for the atomic movement, the crack formation attributed to void coalescence within shear bands can be prevented exhibiting extraordinarily high ductility under compression.

We report on experimental evidence for local amorphization/nanocrystallization at the interfaces between the B2-ordered Ni(Ti,Zr) phase and the NiTiZr phase with P63/mmc during solidification of a multicomponent Ni45Cu5Ti33Zr16Si1 alloy. So far there are several well-known mechanisms for interfacial amorphization in the solid state but no interfacial instability-driven amorphization/nanocrystallization during transition from liquid to solid state has been reported to our knowledge. The curvature of the interfacial area of the ordered Ni(Ti,Zr) phase is locally negative accompanying reverse atomic diffusion. This results in the frustration of the strong ordering tendency of the Ni(Ti,Zr) phase, and induces local amorphization/nanocrystallization.

Pericellular arborization is reported to be the self-regulating structure in sensory ganglia. Although the calcitonin gene-related peptide (CGRP) or substance P (SP) immunoreactive pericellular arborization appeared in the sensory ganglia, there was no available information that CGRP and SP colocalize in this structure. As the attempts to resolve the question described above, the present study was undertaken to identify the coexistence of CGRP and SP in pericellular arborizations of the goat nodose and trigeminal ganglia by double immunohistochemistry. As the results show, CGRP immunoreactivity was present in every pericellular arborization containing SP immunoreactivity in trigeminal ganglia, however, pericellular network containing CGRP or SP immunoreactivity was not present in nodose ganglia. Unexpectedly, a few small satellite elements were observed to contain intense CGRP and SP immunoreactivity at the periphery of CGRP and SP immunoreactive neurones in nodose ganglia. Therefore, these results suggest that CGRP and SP coexist in pericellular arborizations, and that satellite cell as well as pericellular arborization may be involved in intraganglionic regulation of goat sensory ganglia.

In the skull of the Korean native goat, the parietal region was classified into four types by the degree of the fusion of the bones, the os interparietale, the os parietale and the squama occipitalis of the os occipitale, and the structural variations of these fusions. The fusion appeared first in the sutura interparietoparietalis and that of the sutura sagittalis of both ossa parietalia was followed. There was no fusion between the os parietale and the squama occipitalis of the os occipitale. These results suggest that the os interparietale developed independently but fused to the os parietale after birth, and the os parietale were developed as paired bones in prenatal life and then fused together according to age.

Spatial distributions of alloying elements of an Fe-based amorphous ribbon with a nominal composition of were analyzed through the atom probe tomography method. The amorphous ribbon was prepared through the melt spinning method. The macroscopic amorphous natures were confirmed using an X-ray diffractometer (XRD) and a differential scanning calorimeter (DSC). Atom Probe (Cameca LEAP 3000X HR) analyses were carried out in pulsed voltage mode at a specimen base temperature of about 60 K, a pulse to base voltage ratio of 15 %, and a pulse frequency of 200 kHz. The target detection rate was set to 5 ions per 1000 pulses. Based on a statistical analyses of the data obtained from the volume of , homogeneous distributions of alloying elements in nano-scales were concluded. Even with high carbon and strong carbide forming element contents, nano-scale segregation zones of alloying elements were not detected within the Fe-based amorphous ribbon. However, the existence of small sub-nanometer scale clusters due to short range ordering cannot be completely excluded.

We found specific anatomical structure on the fissura nasolacrimalis and fissura nasomaxillaris of the skull of the Korean native goat. It has quite a wide opening on each side of the os nasale and could be classified into four types according to various patterns of articulations of the neighbouring bones.

A minor Co addition to pure Ti can yield a ω-phase distributed along the large β-Ti grain boundaries in the as-cast Ti93Co7 sample. During compression of the sample, a refinement of the ω-phase occurs yielding a unique bimodal grain structure comprising large β and nano-scale ω grains. A large plasticity of ∼30% combined with high strength of the Ti93Co7 sample (∼1.8GPa) can be obtained through local shear dissipation during the refinement of the ω-phase.

Systematic investigations on the microstructural evolution of a bimodal eutectic (Ti70.5Fe29.5)91Sn9 ultrafine composite containing Ti3Sn dendrites upon compression reveal that local deformation of the dendrites dominates the early stage of deformation with a plastic strain of ep=5.8%. After further deformation (ep=10.2%), a wavy propagation of shear bands indicative of dissipation of the shear stress is caused by a rotation of the coarse eutectic structure along the interfaces of the bimodal eutectic structure.

Microstructural investigations on a series of (Ti70.5Fe29.5)100−xSnx alloys with x=5, 7, and 9 reveal that Sn addition is effective in introducing both structural and spatial heterogeneities in ultrafine eutectic composites stemming from a large temperature difference between two eutectic temperatures upon solidification. The microstructural heterogeneities in these ultrafine eutectic composites strongly enhance the room temperature compressive plasticity up to ∼15.7%.

The authors report on the fabrication of complementary thin-film transistor (CTFT) inverters with pentacene (p type) and ZnO (n type) hybrid channels on rf-deposited AlOx dielectrics. All deposition processes were carried out on glass substrates at low temperatures (

Ductile Ti45Cu40Ni7.5Zr5Sn2.5 and Cu47.5Zr47.5Al5 bulk metallic glasses (BMGs) present different work hardening abilities under compression. Microstructural investigations reveal that nanoscale chemical heterogeneities occur throughout the samples. The morphology of the chemically heterogeneous domains in the as-cast Ti45Cu40Ni7.5Zr5Sn2.5 BMG is irregular and significantly interconnected. In contrast, the as-cast Cu47.5Zr47.5Al5 BMG exhibits a spherical morphology of the chemically heterogeneous regions. Furthermore, the distribution of the nanoscale chemical heterogeneity is macroscopically inhomogeneous throughout the material. These findings suggest that the different work hardening abilities of the Ti45Cu40Ni7.5Zr5Sn2.5 and Cu47.5Zr47.5Al5 BMGs possibly originate from the different morphologies and distributions of the chemically heterogeneous regions.

Selected-area electron-diffraction pattern (SADP) and high-resolution transmission electron microscopy (HRTEM) measurements were carried out to investigate the existence and the atomic arrangement of microtwins in hexagonal MnAs ferromagnetic epilayers grown on GaAs (100) substrates with monolayer InAs buffer layers by using molecular beam epitaxy. The magnetization curve as a function of the magnetic field at 5 K showed that the MnAs thin films were ferromagnetic, and the magnetization curve as a function of the temperature revealed that the ferromagnetic transition temperature was as high as 325 K. The SADP and HRTEM results showed that an epitaxial relationship was formed among the hexagonal MnAs layer, the InAs layer, and the zincblende GaAs substrate. Microtwins existed between the MnAs grain boundaries on top of the InAs layers. Based on the SADP and HRTEM results, we present a possible atomic arrangement of the microtwins for the MnAs-InAs-GaAs heterostructure.