Ceramics Published Articles
Resodyn has always encouraged customers, scientists, entrepreneurs, and explorers to use ResonantAcoustic®Mixing (RAM) technology to the fullest extent possible, reaching beyond the existing boundaries of knowledge, experience, or imagination. Inquisitive minds around the globe and across industry have taken – and exceeded – that challenge for many years, eagerly publishing their results.
Abstract: Electromagnetic sensing is a promising technology for precisely locating conductive grid structures that are buried in optical ceramic domes. Burying grid structures directly in the ceramic makes gridded dome construction easier, but a practical sensing technology is required to locate the grid relative to the dome surfaces. This paper presents a novel approach being developed for locating mesh grids that are physically thin, on the order of a mil, curved, and 75% to 90% open space. Non-contact location sensing takes place over a distance of 1/2 inch. A non-contact approach was required because the presence of the ceramic material precludes touching the grid with a measurement tool. Furthermore, the ceramic which may be opaque or transparent is invisible to the sensing technology which is advantageous for calibration. The paper first details the physical principles being exploited. Next, sensor impedance response is discussed for thin, open mesh, grids versus thick, solid, metal conductors. Finally, the technology approach is incorporated into a practical field tool for use in inspecting gridded domes.
Abstract: High density pellets of ZrO2 have been produced by various methods for use as a simulant material for UO2. UO2 is a component in the MOX (metal oxide) fuel for the generation IV nuclear reactors. During the sintering stage for this multi-component fuel, one of its components (americium oxide) is lost due to its high vapor pressure. It would be advantageous if fuel pellets could be prepared at room temperature to a high enough density that a high temperature sintering stage could be reduced or all together eliminated. This paper is a continuation of a previous paper on this subject  that reported on the fabrication of high density pellets of ZrN made by various particle processing routes.
- Production of ceramic nanoparticles through self-propagating high-temperature synthesis (SHS) and their introduction into a metallic matrix to form metal matrix composites
Abstract: Self-propagating high-temperature synthesis (SHS) is a self-sustaining combustion reaction of reactant powders typically in the form of compacted pellets to form a desired product species. The reactants are ignited in one or more locations by several different techniques. After ignition the reaction travels as a wave through the pellet exothermically converting the reactants into products as it propagates. In this case the products are formed as discrete ceramic particles of TiC, Al2O3 and SiC. The goal of this research was to reduce the size of the particles formed by this technique from a diameter of 1-5μm to less than 100nm with the goal of then incorporating these nanoparticles as reinforcements in Al metal matrix composites. To accomplish this, many different SHS principles were studied and their associated variables were changed to reduce the combustion temperature of each reacting system. Several of these systems were investigated and discarded for a number of reasons such as: low ignition or high combustion temperatures, dangerous reaction conditions, or undesirable product densities and morphologies. The systems chosen exhibited low material costs, low combustion temperatures, and a wide range of stabilities when lowering the reaction temperature. The reacting systems pursued were based around the aluminothermic reduction of TiO2 in the presence of carbon to form TiC and Al2O3. The combustion temperature of this reaction was reduced from 2053ºC to less than 1100ºC, which had a corresponding effect on the particle size of the products, reducing the average diameter of the particles to less than 100nm. This was accomplished by providing high heating rates, controlling the green density and adding diluents to the reaction such as Al, TiC, SiC or Al2O3. Cooling experiments were also investigated, but the cooling rate was found to have no effect on the particle size.