The local atomic structures in glassy, supercooled liquid and quasicrystalline phases for a Zr70Pd30 binary alloy have been examined by the x-ray diffraction method. It was found that the local atomic structure in the glassy phase can be identified as the distorted icosahedral-like structure around Zr and remains almost unchanged by the phase transformation into the supercooled liquid. In the formation process of the icosahedral phase, approximately one Zr atom substitutes with one Pd atom in this local structure. This kind of atomic rearrangement may improve the perfectibility of the as-quenched icosahedral-like cluster, leading to the phase evolution of the icosahedral phase.

Photoluminescence (PL) measurements were performed on p-Cd0.96Zn0.04Te single crystals to investigate the dependence of the excitons on temperature. The activation energies and the longitudinal acoustic parameters of the excitons were determined from the temperature dependence of the PL spectra and were in reasonable agreement with the theoretical calculations. These results can help improve understanding for the application of p-CdxZn1–xTe single crystals in optoelectronic devices.

A methodology is developed which extends the combinatorial approaches to structural materials research and development. This high-efficiency methodology employs diffusion couples and “diffusion multiples” to create large variations (libraries) of compositions in bulk samples for fast and systematic surveys of bulk properties. These composition libraries coupled with microanalytical techniques such as electron probe microanalysis, electron backscatter diffraction analysis, and nanoindentation tests can be used for efficient surveys of phases, equilibria, diffusion coefficients, precipitation kinetics, properties, and composition–phase–property relations (such as solution hardening and strengthening effect) for accelerated design of multicomponent alloys.

A family of lanthanide silicates adopts an oxyapatitelike structure with structural formula Ln9.33 0.67(SiO4)6O2 (Ln = La, Sm, Nd, Gd,   = vacancy). The enthalpies of solution, ΔHS, for these materials and their corresponding binary oxides were determined by high-temperature oxide melt solution calorimetry using molten 2PbO B2O3 at 1078 K. These data were used to complete thermodynamic cycles to calculate enthalpies of formation from the oxides, ΔH0 f-oxides (kJ/mol): La9.33 0.67(SiO4)6O2 = 776.3 ± 17.9, Nd9.33 0.67(SiO4)6O2 = 760.4 ± 31.9, Sm9.33 0.67(SiO4)6O2 = 590.3 ± 18.6, and Gd9.33 0.67(SiO4)6O2 = 446.9 ± 21.9. Reference data were used to calculate the standard enthalpies of formation from the elements, ΔH0 f (kJ/mol): La9.33 0.67(SiO4)6O2 = 14611.0 ± 19.4, Nd9.33 0.67(SiO4)6O2 = 14661.5 ± 32.2, Sm9.33 0.67(SiO4)6O2 = -14561.7 ±; 20.8, and Gd9.33 0.67(SiO4)6O2 = -14402.7 ± 28.2. The formation enthalpies become more endothermic as the ionic radius of the lanthanide ion decreases.

It is shown that the substitution of reduced modulus for specimen modulus in the analysis equations for nanoindentation test data is valid. The methods of analysis use the slope of the unloading force–depth response which is assumed to be elastic. Because of this utilization of the slope or unloading stiffness, it makes no difference whether or not the deflection of the indenter is accommodated explicitly or transferred to that occurring within the specimen by artificially reducing the specimen modulus from its true value to lower value, the reduced modulus.

Large-scale SiO2 nanowires were synthesized by using a simple but an effective approach at low temperature. Scanning electron microscopy, transmission electron microscopy, and x-ray photoelectron spectroscopy were employed to characterize the samples. The results indicated that SiO2 nanowires with a uniform diameter of about 20 nm and a length up to 10 μm have been synthesized. Photoluminescence measurement showed that the SiO2 nanowires emitted blue light at 2.8 and 3.0 eV. The possible growth process of the SiO2 nanowires is discussed. Using this method, large panels of SiO2 nanowires can be made under conditions that are suitable for device fabrication.

We studied in detail the chemical structure evolution of Pb(Zr1−x, Tix)O3 (PZT) thin films on Pt electrodes during the initial thermal steps of their preparation using an alkoxide-based sol-gel process. Absorption-reflection Fourier transform infrared spectroscopy (AR-FTIRS) was used to monitor chemical reactions occurring in the films on a real temperature scale. We demonstrate that the chemical state of the pyrolyzed film strongly depends on pyrolysis conditions and can have a large effect on the orientation selection in the film. First, residual acetate groups, resulting from incomplete decomposition of the Pb acetate precursor, strengthen the (111) PZT texture component after crystallization. Second, OH bonds, which are seen to remain in the film after pyrolysis under specific conditions, are seen to strengthen the intensity of the PZT(100) reflection. Possible mechanisms behind these observations are discussed.

TiB2 thin films demonstrate considerable potential for use as protective overcoats in the magnetic recording industry due to their excellent mechanical and tribological properties and good chemical and thermal stability. In the many studies performed on TiB2 films, the relative effectiveness of ultrathin TiB2 films has not been systematically investigated for very thin TiB2 films. In the present investigation, film stress and microstructure in as-sputtered and annealed ultrathin TiB2 films were investigated as a function of thickness. Ultrathin TiB2 films, as thin as 5 nm, were observed to adequately protect an underlying magnetic layer from oxidation up to 400 °C.

We investigated the transformation behavior from glassy to Zr2Ni phase in the Zr65Al7.5Ni10Cu17.5 glassy alloy with a low oxygen content below 400 ppm mass%. The mostly single face centered cubic Zr2Ni phase precipitated as a primary phase at the initial crystallization stage. The Zr2Ni particles had a cubical morphology in the diameter range of 300 to 500 nm and were in an isolated state for the sample annealed at the temperature near crystallization temperature. A significant redistribution leading to the enrichment of Zr and Ni into the Zr2Ni phase is confirmed. Moreover, it is recognized that Cu and Al are rejected from the Zr2Ni phase. The compositional differences of Zr, Al, Ni, and Cu between the Zr2Ni and remaining glassy phases are in the range of 1.5 to 5 at.%. It is strongly suggested that such a significant redistribution of the constitutional elements restrains the nucleation and growth of crystalline phases. It is one of the important factors for the stabilization of the glassy state in Zr–Al–Ni–Cu alloy.

Precise control of porosity and microstructure of porous ceramics is essential. This paper describes a method for the preparation of porous ceramics with porosity from 0.0 to 0.4. The ceramics were prepared via hot pressing a powder mixture to a definite dimension, and the porosity was easily adjusted by the powder amount. As examples, porous Si3N4 or SiC ceramics were produced by powder mixtures that contained Si3N4 or SiC and a sintering additive of oxide. It was demonstrated that the present method is advantageous for producing ceramics with controllable porosity and microstructure.

The underlying theory behind the extraction of elastic modulus and hardness from the unloading load–displacement data obtained with a spherical indenter was explored in detail. A formal treatment of the effect of indenter elasticity was given, and the validity of the use of the reduced or combined modulus in analytical treatments was verified. The “Oliver and Pharr” method and the “Field and Swain” methods of analyses were compared in detail and shown to be equivalent.

Nanorods Bi3Se4 were synthesized directly through the reaction between BiCl3 and elemental selenium in an autoclave with hydrazine hydrate as solvent at 165 °C for 10 h. X-ray powder diffraction patterns, x-ray photoelectron spectra, and transmission electron microscope images show that the products are well-crystallized hexagonal Bi3Se4 nanorods. The solvent hydrazine hydrate played an important role in formation and growth of Bi3Se4 nanorods. The possible reaction mechanism was proposed.

A new synthesis route, based on internal oxidation reactions in multiphase alloys, is proposed for the controlled production of near-surface, complex ceramic-ceramic or ceramic-metallic composite structures. Using this approach, a microdispersion of a complex nitride perovskite, Cr3PtN, was formed in Cr2N or Cr(Pt) by internal nitridation of a two-phase Cr(Pt) + Cr3Pt precursor alloy. A framework for use of this phenomenon to synthesize island micro- (and potentially meso- or nano-) composite functional surface structures is presented.

A ferromagnetic film composed of carbon matrix and dispersed fine iron particles was prepared by heating a polyimide film containing iron complex at temperatures up to 1000 °C. The particles were formed and distributed homogeneously on the film surfaces by heat treatments at 600 °C and above, and inside the films at 700 °C and above. The particles were α–Fe, γ–Fe (or austenite), and Fe3C with fractions of about 7:2:1 in the films heated at 800 °C and above. The mean crystallite sizes of α–Fe and γ–Fe (or austenite) particles were evaluated to be 19 and 15 nm in the film heated at 800 °C, and 32 and 30 nm at 1000 °C, respectively. The films heated at 600 °C and below were superparamagnetic, while those at 700 °C and above were ferromagnetic, but both components existed in all films. The iron particles promoted the growth of carbon crystallites in the films; i.e., the interlayer spacing was about 0.341–0.343 nm and mean crystallite size 4.0–6.5 nm for the films heated in the range of 700 to 1000 °C. Pores were observed on the surfaces and cross sections of the carbonized films, and they seemed to be loopholes of the clusters. Iron oxides were scarcely formed in the films, even after being kept for a long duration at room temperature in atmosphere.

Effects Cu and Ni additions on Au embrittlement of eutectic Sn–Pb solder interconnections during a solid-state aging treatment were evaluated using a ball shear testing method. The addition resulted in a formation of Au-containing ternary intermetallic compounds, either Au–Sn–Cu or Au–Sn–Ni phase, inside the solder matrix during aging treatment. The fracture energy of the solder interconnection containing 2.9 wt% Cu remained almost the same up to 200 h of aging treatment at 150 °C, demonstrating the possibility of suppressing the Au embrittlement by forming ternary intermetallic phases inside the solder matrix.

Aluminum nitride powder was synthesized by a combustion synthesis method using various additives. Each additive was mixed with Al powder, and the powder mixture was then pressed into a compact. The combustion reaction was ignited by heating the compact under N2 atmosphere of 0.4 MPa. Additives containing halogens were found to have a catalytic effect on the combustion reaction. High product yields were obtained when using additives of NH4X, CO(NH2)2, CH3(CH2)16COOH, and CO2H(CH2)2CO2H. In all these cases, eggshell-like skins were observed to form on the Al particles at the early stage of combustion. The catalytic effect, formation of the eggshell-like skins, and their effects on the combustion process were investigated and discussed.

Porous silicon nitride with aligned fibrous grains was fabricated by sinter-forging technique, where uniaxial pressure was applied to achieve a specific density after soaking at elevated temperatures. Fibrous silicon nitride grains were formed during the soaking, and the grains were aligned by the subsequent forging. As the result, a specimen with strongly aligned fibrous silicon nitride grains was successfully fabricated. The specimen with a relative density of 76% exhibited high bending strength of 778 MPa.

The corrosive wearing behavior of the Co–Cr–W alloy in liquid zinc was investigated using a specially designed wearing test machine. Its corrosion rate and wear rate during corrosive wearing process with different conditions were analyzed. The corrosive wearing mechanism of the Co–Cr–W alloy was investigated by analysis on its sliding surface using scanning electron microscopy, energy dispersive spectrometry, and microhardness sclerometer. The experimental results led to the following conclusions: (i) The corrosion of the Co–Cr–W alloy is accelerated by wearing process in the liquid zinc. (ii) The liquid zinc provides obvious lubrication to the sliding surfaces of this alloy and then reduces its wearing rate during the corrosive wearing process. (iii) Its corrosive wearing rate is increasing sharply with increasing temperature of the liquid zinc. (iv) The corrosive wearing of the Co–Cr–W alloy is caused by preferential corrosion of the eutectic phases in this alloy and fatigue cracking of the worn surface. The fatigue wearing of this alloy is directly due to the synthetic effect of strain hardening of the layer on and under sliding surface and serious stress corrosion in the crack tips during the corrosive wearing period.

Nuclear resonance reaction analysis has been applied for the first time to measure the development of the hydrogen depth profile in the early stages of hydration of tricalcium silicate using the 1H(15N,αγ)12C reaction. The surface layer had an H concentration and thickness consistent with a few unit cells (1.1 nm) of tobermorite-like material. The inner regions exhibited diffusion-controlled growth with time until the hydrogen concentration approaches that of the surface layer at 4.25 ± 0.07 h. This event marked the end of the induction period and the onset of the rapid hydration reaction period.

Composite separation membranes of poly(dimethylsiloxane) (PDMS) containing well-dispersed silicalite particles of 50 nm were successfully prepared and applied to the preferential pervaporation of acetic acid over water. The nanocomposite membranes showed improvement on both separation factor and permeation flux for the pervaporation process, as compared to plain PDMS membranes and composite membranes containing silicalite particles of 5 μm. The improvement can be attributed to higher readily accessible specific surface area and higher sorption selectivity toward acetic acid of the nano-size silicalite particles. Improvement on membrane thermal stability was also acquired through incorporation of nano-size silicalite particles.