For microelectronic circuits, the main type of failure is thermal fatigue. Therefore, the search for matched coefficients of thermal expansion (CTE) of packaging materials in combination with a high thermal conductivity is the main task for developments of heat sink materials electronics, and good mechanical properties are also required. The aim of this work is to develop copper matrix composites reinforced with carbon nanofibers to meet these requirements. In this paper, a technology for obtaining a homogeneous mixture of copper and nanofibers will be presented and the microstructure and properties of consolidated samples will be discussed.

The decrease of the distance between particle centers due to the growth of the sinter necks can be explained by the well known two-particle model. Unfortunately this model fails to provide a comprehensive description of the processes for 3D specimens. Furthermore, there is a significant discrepancy between the calculated and the measured shrinkage because particle rearrangements are not considered. Only the recently developed analysis of the particle movements inside of 3D specimens using micro focus computed tomography (μCT), combined with photogrammetric image analysis, can deliver the necessary experimental data to improve existing sintering theories. In this work, μCT analysis was applied to spherical copper powders. Based on photogrammetric image analysis, it is possible to determine the positions of all particle centers for tracking the particles over the entire sintering process and to follow the formation and breaking of the particle bonds. In this paper, we present an in-depth analysis of the obtaine data. In the future, high resolution synchrotron radiation tomography will be utilized to obtain in-situ data and images of higher resolution.

With the capability of net shaping for complex 3D geometry, powder injection molding (PIM) is widely used for automotive parts, electronics and medical industry. In this study, an ultrasonic dental scaler tip produced by machining process was redesigned for the PIM process. An injection mold was designed and machined to produce the dental scaler tip by the PIM process.

Powder Injection Molding (PIM) has recently been recognized as an advanced manufacturing technology for low-cost mass production of metal or ceramic parts of complicated geometry. With this regards, design technology of dental scaler tip PIM mold, which has complex shape, with the help of computer-aided analysis for powder injection molding process was developed. Compter aided analysis results, such as filling pattern, weldline formation, and air vent position prediction were investigated and eventually showed good agreements with experimental results.

The n-type compound was newly fabricated by gas atomization and hot extrusion, which is considered to be a mass production technique of this alloy. The effect of powder size on thermoelectric properties of 0.04% doped alloy were investigated. Seebeck coefficient and Electrical resistivity increased with increasing powder size due to the decrease in carrier concentration by oxygen content. With increasing powder size, the compressive strength of alloy was increased due to the relative high density. The compound with size shows the highest power factor among the four different powder sizes. The rapidly solidified and hot extruded compound using powder size shows the highest compressive strength.

Pure and stable YAG powders were synthesized by a PVA (polyvinyl alcohol) polymer solution technique. PVA was used as an organic carrier for the precursor ceramic gel. The precursor gels were crystallized to YAG at relatively a low temperature of . The synthesized powders, which have nano-sized primary particles, were soft and porous, and the porous powders were ground to sub-micron size by a simple ball milling process. The ball-milled powders were densified to 94% relative density at for 1h. In this study, the characteristics of the synthesized YAG powders were examined.

Nb-Ti alloys were hydrogenated to prepare fine and contamination-free powders. Cracks were introduced in the alloys when they were annealed at 1473 K and cooled in a hydrogen atmosphere. The fragments produced by hydrogen-induced cracking are brittle and the friability enhanced with the Ti content of the alloy, which is beneficial for further refinement of particle size. We also demonstrate that Nb-Ti powders with the average particle size less than 1 m can be produced by ball milling at a temperature lower than 203 K. Furthermore, hydrogen-free powders can then be obtained by annealing above the temperature corresponding to hydrogen desorption from Nb solid solution.