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Relatively low strength and fracture toughness of ceramics have restricted their applications. Various solutions have been studied to overcome the abovementioned drawbacks. One of the most sophisticated and promising solution is production of multilayer ceramic composites. High hardness, heat and wear resistance, low electrical and thermal conductivity, and resistance to chemical attacks are the most important characteristics of Al₂O₃. Therefore, it is a common candidate for various industrial applications. Multilayer alumina-zirconia composites were made using two methods of isostatic and hydraulic compaction of dry ceramic powders. The green articles were conventionally sintered at 1420, 1550 and 1650°C for 3h. The microstructure and density of composites were investigated. The results show that the pressing method and sintering temperature have a relatively moderate effect on the microstructure and density of the sintered samples.

The present electronic industry requires capacitors having high capacitance with lower volume and space, high reliability and low leakage current. The solid tantalum capacitor ideally meets such requirements. In the present paper, the electrical characterization of tantalum anodes prepared from sodium reduced tantalum powder has been described. The capacitance, DC leakage current are measured for tantalum anodes made with different particle sizes of powders using the LCR Meter and DC Leakage Tester and compared with the physical and chemical properties. Interestingly, it was found that the DC leakage current decreases with decrease in particle size on contrary to the surface area. Besides, a trade-off appears imminent to establish the formation voltage and DC leakage current relationship.

This research work is an insight into the various properties of liner materials utilized in landfill sites to control the leachate. Although expansive clay soil is inorganic, it is problematic. The soil owes this aspect to erratic fluctuations in its behavior due to the movement of water. Urbanization, increase in population and industries generate enormous amounts of waste in different forms. Disposal of these wastes in the landfill without any scientific manner creates a major problem to the surrounding soil and groundwater. In this study, an attempt was taken to identify the effect of soil properties and groundwater quality due to the continuous generation of leachate in the dumping sites. To prevent such an environmental problem, highly impermeable sand–bentonite mixture is used as a liner material in the waste disposal sites. Therefore, various mixtures of sand–bentonite were prepared by varying sand contents and different sieve sizes, i.e. 2–0.075mm; 2–0.425mm and 0.425–0.075mm were used. And also to improve the strength and hydraulic conductivity of the liner materials, discrete random fiber is mixed with various proportions to these mixtures and examined.

We briefly describe how mean-field glass models can be extended to the case where the bath and friction are non-thermal. Solving their dynamics, one discovers a temperature with a thermodynamic meaning associated with the slow rearrangements, even though there is no thermodynamic temperature at the level of fast dynamics. This temperature can be shown to match the one defined on the basis of a flat measure over blocked (jammed) configurations. Numerical checks on realistic systems suggest that these features may be valid in general.

The flow pattern of loose powders indented by a rigid punch in an open cylindrical die was studied using the discrete element method (DEM) and the finite element method (FEM) using the Drucker-Prager/CAP material model. The results are compared with those obtained through X-ray microtomography studies of particle movement during the deep penetration of a granular material. The density distribution of the granular material and trajectories of the particles during the deep penetration of the punch are analyzed. It is observed that in the vicinity of the punch, several kinds of flow patterns occur simultaneously, and the shear produces a relatively low density. Typical particle displacement and particle density distributions can be observed in both the numerical simulations and experimental studies. This study demonstrates that DEM and FEM can capture the main features of the powder flow behaviour during low-pressure compaction.

The compaction of particulate materials to form tablets is increasingly employed as a final dosage form for functional products due to its simplicity and low cost. However, the functionality of some products may be impaired due to the high compression pressures required. The general aim of the current study is to understand the relationship between the mechanical properties of single feed particles (< 100 µm) and their compaction behaviour in order to produce tablets at low compression pressure with acceptable strength. The materials studied were pharmaceutical excipients, comprising three enteric polymer particles and three different powders in the form of agglomerates. The mechanical properties of the individual particles or agglomerates were determined by a micromanipulation technique. The samples were also compacted in cylindrical tableting dies. It was observed that there was a strong correlation between the forces required to cause the fracture of the single particles and those derived from the compaction measurements as determined using an existing analysis.

Compaction and the corresponding viscoelastic behaviors of woven fiber reinforcements are essential to determine the mechanical properties of composite components. Current reported works separately studied the viscoelastic behaviors in partial stage of the compaction process. In contrast, here, we propose a uniform viscoelastic model that can describe the viscoelastic responses in all stages. Systematical experiments of carbon and glass woven fiber reinforcements demonstrate the effectiveness of this viscoelastic model. Moreover, the significances of the model parameters and their underlying relations are clearly revealed. The time constants are not equal in different stages due to different roles of fiber friction played. The relationship among time constants in different stages is found and is experimentally demonstrated. Stress constants strongly depend on the initial stress and types of fiber reinforcements. The relationships between stress constants in all stages are also obtained. The proposed theoretical model here provides a potential and promising approach to understand the viscoelastic responses of woven fiber reinforcements in compaction process.

We briefly describe how mean-field glass models can be extended to the case where the bath and friction are non-thermal. Solving their dynamics, one discovers a temperature with a thermodynamic meaning associated with the slow rearrangements, even though there is no thermodynamic temperature at the level of fast dynamics. This temperature can be shown to match the one defined on the basis of a flat measure over blocked (jammed) configurations. Numerical checks on realistic systems suggest that these features may be valid in general.

By in-situ compaction test in the construction site for the blasted material with the 80.0cm thickness of placing and spreading and different compacted times, the compaction construction technology of blasted material in dam was studied and related construction parameters was suggested. The study showed that: when the watering content increased from 0.0% to 10.0%, the indexes, including average compacted settlement, porosity and dry density, of the blasted material was influenced obviously with the increasing of compaction times. But when the watering content further increased from 10.0% to 15.0%, there was no obvious change of the above indexes with the increasing of compaction times, particularly, when the watering content increased from 0.0% to 15.0%, it seemed that there was a little influence of the water content and indexed of granular with the change of compaction times. It satisfied with the design requirement with the following suggested construction technique and related parameters: when the blasted material is as the compacted materials, it is placed and spread by the step-forward technique, the thickness of placing and spreading is 80.0cm, the watering content is 5.0% or 10.0% (watering content is controlled by volumetric method), then it is compacted 10 times or 8 times according to different watering contents by the smooth drum vibratory roller with the 32 tons at the velocity of 2.8 km/h, during the compaction, the forward and backward method with lapped joint width is about 1/10 vibration wheel’s width is adopted.