Ti(C, N)-Based Cermets with Two Kinds of Core-Rim Structures Constructed by β-Co Microspheres

Ti(C, N)-based cermet materials represent the best choice of materials for the manufacturing industry and military products. In this study, we use cubic β-cobalt(β-Co) as the binder phase to strengthen constructed cermets. At the same time, to optimize the microstructure, (Ti, W, Mo, Ta) (C, N) powders are added to form two kinds of core-rim morphologies. Here, β-cobalt powders with face-centered cubic structures are obtained by the solid-phase reaction of high-energy ball milling. A solid-phase chemical reaction and a carbothermic reduction-nitridation method are used to prepare the (Ti, W, Mo, Ta) (C, N) powders. In our process, first we mix the cobalt and (Ti, W, Mo, Ta) (C, N) powders; then we press the powder mixtures into rectangular samples and sinter them in a pressure sintering furnace to obtain Ti(C, N)-based cermets with two kinds of core-rim structure, that is, black core/white rim and white core/gray rim. The results show that the new cermets demonstrate excellent toughness and performance.

Particulate copper electrodeposited on carbon felt for degradation of low concentration of methyl iodide in liquid radioactive wastes

In this work, the study of copper particles deposition on to carbon felt was presented by pulse electrodeposition method to electrochemically degrade methyl iodide (CH3I, 1 mg L−1) in aqueous solution. In order to solve the problems linked to the heterogeneous potential distribution in the 3-D porous structure, which lead to the so-called ‘black core’, we successfully used low concentration of copper salt (1 mM) and negative deposition potential (−2.5 V) to obtain Cu-nanoparticles/carbon felt (Cu-nano/CF) electrode, the copper coating improved the specific surface area of carbon felt from ∼0.07 to 0.7 m2 g−1 with high catalytic activity. Results show that 98.1% of CH3I can be removed with the Cu-nano/CF electrode in 120 min.

Optimum Bloating-Activation Zone of Artificial Lightweight Aggregate by Dynamic Parameters

The purpose of this study is to compare the bloating mechanism of artificial lightweight aggregate under sintering and rapid sintering conditions to identify the factors behind the bloating of the lightweight aggregate under these sintering conditions, and to find suitable temperature ramping conditions. The aggregate had an average particle size of 10 mm as formed using acid clay, and it was fired by a rapid sintering method and a normal sintering method. The bulk density and water absorption ratio of the specimen were measured, and the cross section was observed. No black core was observed under the rapid sintering condition, and it was lightened at an inflection point of 1150 °C. A reduction in the bulk density was observed in a shorter period of time when the input temperature was high under the normal sintering conditions. Regardless of the input temperature, the bulk density change was divided into three sections and a bloating-activation zone was observed in which the density abruptly decreased.

Research on Effect of Cr3C2 Addition on Microstructure and Mechanical Properties of Ti(C,N)-Based Cermets

Four Ti (C,N)-based cermets with Cr3C2 content of 0.3%, 0.6%, 0.9% and 1.2 % in mass ratio were sintered in vacuum at 1430oC, 1450oC, 1465oC and 1480oC. The mechanical properties of the specimens were determinted and microstructures were observed using the scanning electron microscope (SEM) to study the effect of Cr3C2 content on mechanical properties and microstructure. The results show that the four Ti (C,N)-based cermets sintered at 1465oC have the best overall mechanical properties; and among them, the cermet with 0.6% Cr3C2 has the best overall mechanical properties, i.e. transverse rupture strength (TRS) 1967MPa, hardness 1556HV and fracture toughness (KIC) 9.5MPa.m1/2. With the increase of Cr3C2 content, the black core volume fraction firstly increases and then decreases, the white core decreases in a progressive and continuous manner, the rim phase firstly increases and then decreases, the binder phase firstly decreases and then increases.

A Comparative Study on the Physical Properties of Artificial Aggregates Made from Acid Clay and Dredged Soil

Artificial aggregates (AAs) were manufactured from the acid clay (waste bentonite) and dredged soil produced at a thermal power plant by sintering at 600~1200°C for 10min. And those specimens were compared with respect to their bloating ability. The aggregates of acid clay had well-developed black core and uniform macro pores. The specific gravity of the AAs of acid clay increased with sintering temperature at 600~1000°C due to densification, but dramatically decreased at 1100°C, and at this temperature, the AAs showed bloating. The specific gravity and water absorption of the aggregates of dredged soil decreased with sintering temperature at 600~1000°C, indicating that the dredged soil has the ability to enlarge the sintering temperature range, favorable for the mass production process. The specific gravity of the AAs fabricated in this research ranged 0.8~2.0 and the water absorption ranged 4~26%, which was sufficient for various applications, such as functional membranes, light weight construction, smart soil, sound absorption and insulation fields etc..

Holographic shell model: Stack data structure inside black holes?

Rather than tiling the black hole horizon by Planck area patches, we suggest that bits of information inhabit, universally and holographically, the entire black core interior, a bit per a light sheet unit interval of order Planck area difference. The number of distinguishable (tagged by a binary code) configurations, counted within the context of a discrete holographic shell model, is given by the Catalan series. The area entropy formula is recovered, including Cardy's universal logarithmic correction, and the equipartition of mass per degree of freedom is proven. The black hole information storage resembles, in the count procedure, the so-called stack data structure.

Influence of Addition of Waste Glass as a Fluxing Agent on the Bloating Phenomenon of Artificial Aggregates Fabricated from Coal Bottom Ash

The artificial aggregates (AAs) were manufactured from the parent batch powders consisting of bottom ash produced at thermal power plant and dredged soil by direct sintering method at 1050~1200°C for 10min. The bloating phenomenon could be occurred in AAs due to a gas-capturing caused by large quantity of liquid formed at the specimen surface. Increasing the amount of the Na2O added enlarged the area of black core and size of the macro pores in the aggregates. The inside black core got out of the surface of the specimens sintered at 1200°C showing the rugged and cracked surface, but this morphology did not cause a water absorption to increase.