An experimental study on the adhesion of thin films was conducted for the ultraviolet (UV)-cured SiOC films on Si substrate by examining the mechanical energy balance during the indentation process combined with atomic force microscopy observation. The effect of UV cure on the interfacial delamination toughness and the structure of the SiOC films are discussed. The energy release rate of the SiOC film/Si substrate interfacial delamination increases with the increases in the time of UV curing, indicating that the indentation method is efficient to examine the adhesion of coating. As the UV curing time increases, the film thickness and the Si–CH3 bond structure decrease, whereas the SiO2 network structure develops and the mechanical properties of the film are improved. Furthermore, the energy release rate of SiOC film/Si interfacial delamination is well correlated in a proportional manner to the Young's modulus of the film.

Synchrotron x-ray μ-tomography has been used to reconstruct the three-dimensional view of a rough surface extracted from a heterogeneous ceramic coating composed of Pr2NiO4+δ. Radiographs with a resolution of 0.7 μm have been recorded at T = 300, 600, and 900 K. The analysis of surface geometry makes use of the geometrical optic approximation up to T = 900 K possible. Subsequently, a large number of rays (105) are impinged onto the numerical surface, as revealed by x-ray tomography, to reproduce the normal emissivity of the coating. This normal emissivity was obtained beforehand by infrared emittance spectroscopy at T = 1000 K. Comparison of the two approaches suggests that the optical contribution of the coating micropores can be integrated into the ray tracing code. The effective medium approximation is used for this purpose. Finally, the applicability of this hybrid approach is discussed.

Thin films of c-axis-oriented LiCoO2 were epitaxially grown by pulsed laser deposition (PLD). The ablation laser conditions greatly affect the crystal quality of the epitaxial LiCoO2 thin films. In addition, high-quality LiCoO2 thin films were found to grow without any impurity phases under relatively low oxygen partial pressure, although high pressure had been often selected to suppress the formation of Co3O4 with a lower valence state as an impurity. This result clearly indicates that the ablation laser conditions are an essential growth parameter, and that composition control is indispensable to grow high-quality complex compound thin films by PLD.

A new Pd79Au1.5Ag3Si16.5 bulk metallic glass was successfully synthesized in a maximum casting thickness range to 3 mm. Upon heating, the single glassy phase decomposed into Pd-rich crystalline phases and a Si-rich amorphous phase due to solute partitioning. In addition to high thermal stability, this bulk glassy alloy also exhibited a high degree of ductility and excellent corrosion resistance, showing potential applications as biomaterials.

Bismuth telluride (Bi2Te3) systems containing 2%, 4%, and 8% of iron were prepared using a low temperature wet chemical method. Iron oxide nanoparticles were formed when the samples were heated in hydrogen at 250 °C for at least six hours. The samples were characterized by x-ray diffraction, magnetization, magnetic susceptibility, x-ray photoelectron spectroscopy, Mössbauer spectroscopy, and wet chemical analysis measurements. The nanoparticles of iron oxide were identified as γ-Fe2O3 with a particle size of ˜5 nm.

Electron backscatter diffraction analysis was used to compare the crystal orientation of β-Sn grains in Ni(P)/Sn–0.5Cu/Cu and Ni(P)/Sn–1.8Ag/Cu joints before and after aging. In Ni(P)/solder/Cu joints, the solder composition (Cu versus Ag) significantly affects β-Sn grain orientation. In Ni(P)/Sn–0.5Cu/Cu, there are two types of small columnar grains grown from Ni(P) and Cu under bump metallurgy with a high-angle grain boundary crossing the joint closer to the Ni side; in contrast, Ni(P)/Sn–1.8Ag/Cu has large grains with low-angle boundaries. During thermal aging at 150 °C for 250 h, the Ni(P)/Sn–0.5Cu/Cu joints undergo a more significant microstructural change than the Ni(P)/Sn–1.8Ag/Cu joint. Additionally, obvious ledges developed along the high-angle grain boundary between the upper and lower areas in the Sn–0.5Cu joint.

It has been shown that the stability of shear banding and plasticity of bulk metallic glasses (BMGs) can be strongly influenced by the machine stiffness. Here, we demonstrated that the practice of adding a frame parallel to the sample is quantitatively equivalent to increasing the machine stiffness by the frame stiffness. A series of carefully designed experiments were conducted to verify such an effect, showing controllably enhanced plasticity of BMG samples.

The tensile deformation of anisotropic porous copper with unidirectionally oriented cylindrical pores was investigated by an acoustic emission method. In the loadings parallel and perpendicular to the orientation direction of the pores, many cracks are formed after yielding and they strongly affect the deformation. The formed cracks rapidly grow and connect with each other near the peak stress of the stress–strain curve, thereby leading to final fracture. Crack formation is easier under perpendicular loading than under parallel loading, because high stress concentration and stress triaxiality occurs around the pores. As a result, the strength and elongation for perpendicular loading are much smaller than those for parallel loading. Furthermore, in the case of perpendicular loading, the localized deformation around pores drastically decreases the plastic Poisson's ratio. These results indicate that a porous copper macroscopically behaves as a semibrittle material under perpendicular loading, while the porous copper exhibits ductility under parallel loading.

We describe progress in understanding the effect of simulated chemical-mechanical planarization (CMP) slurry chemistry on the evolution of defects and formation of damage that occurs during CMP processing. Specifically, we demonstrate the significant effect of aqueous solution chemistry on accelerating crack growth in porous methylsilsesquioxane (MSSQ) films. In addition, we show that the same aqueous solutions can diffuse rapidly into the highly hydrophobic nanoporous MSSQ films containing interconnected porosity. Such diffusion has deleterious effects on both dielectric properties and the acceleration of defect growth rates. Crack propagation rates were measured in several CMP solutions, and the resulting crack growth behavior was used to qualitatively predict the extent of damage during CMP. These predictions are compared with damage formed during actual CMP processes in identical chemistries. We discuss the effects of both the high and low crack growth rate regimes, including the presence of a crack growth threshold, on the predicted CMP damage. Finally, implications for improved CMP processing were considered.

Applying glass fluxing and cyclic superheating, rapid solidification of undercooled Ni–15at.%Cu alloy was performed by rapidly quenching the sample after recalescence. The evolution of microstructure and microtexture has been analyzed. At both low and high undercoolings, well-developed dendrites, within and around which are distributed by the fine equiaxed grains, are observed. At low undercooling, the completely grain-refined microstructure shows a highly oriented texture without annealing twins, whereas at high undercooling a fully random texture as well as a number of annealing twins is observed. On this basis, all the possible mechanisms for grain refinement, as well as their effects on the microstructure formation, were discussed. The grain refinement at both low and high undercoolings is concluded to originate from dendrite fragmentation. Particularly, at high undercooling, recrystallization, as a consequence of dendrite deformation (by fluid flow) and dendrite fragmentation (which provides grain boundary sites for recrystallization nucleation and for the “appearing” recrystallized grains), occurs and plays a role in the grain refinement and the formation of fully random texture.

Ultra fine CuO nanoparticles in the range of 2 ± 0.2 nm were synthesized by the supercritical hydrothermal method in a batch reactor. It was demonstrated that elevating the pH of the Cu2+ precursor solution to around 6 (neutral condition) not only does not lead to excessive agglomeration of the particles, but also reduces particle size and in general promotes their nanoscale characteristics. Prepared nanoparticles were immobilized in the biopolymeric matrix of barium alginate and calcined at different temperatures resulting in microspherical granules of high porosity and elevated mechanical strength. The fabricated samples were characterized using x-ray diffractometry (XRD), transmission and scanning electron microscopy (TEM and SEM), nitrogen adsorption analysis (BET), mechanical testing, and temperature programmed reduction (TPR). It was found that topochemical models based on a nucleation growth mechanism fail in proper fitting of the TPR data. Instead, a generalized Sestak model in which different physicochemical mechanisms such as the mass action law are taken into account gives a satisfactory regression of the kinetics behavior.

Detailed understanding of growth termination in vertically aligned single-walled carbon nanotubes (SWNTs) made via supergrowth, or water-assisted growth, remains critical to achieving the ultralong SWNTs necessary for next-generation applications. We describe the irreversible catalyst morphology evolution that occurs during growth, and which limits the lifetime of surface supported catalysts. Growth termination is strongly dependent on growth temperature, but not sensitive to C2H2:H2O ratio. In addition to both planar Ostwald ripening of small (sub-5 nm) Fe catalyst particles and diffusion of metal atoms into the alumina support, other features that contribute to growth termination or deceleration are described, including center-of-mass particle motions and coalescence of smaller species of surface supported Fe nanoparticles. Additionally, a temperature-induced structural transition in the alumina catalyst support is found to be coincident with abrupt growth termination at temperatures of 800 °C and higher. In situ electron microscopy observations are used to directly support these observations.