In situ reaction method was undertaken to fabricate A1N-BN composites in this paper. Factors including temperature, heat preservation time, and the ratio of Al to BN were investigated in this system. DTA and XRD were ...
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In situ reaction method was undertaken to fabricate A1N-BN composites in this paper. Factors including temperature, heat preservation time, and the ratio of Al to BN were investigated in this system. DTA and XRD were employed to character the phases of production. SEM was conducted to observe the microstructure of the samples. The results showed that the grains tended to perfect with the increasing of the sintering temperature and soaking time. Optimum parameters were temperature of 1000°C and 1.5 h for soaking time.
AlN was synthesized by in situ reaction with Al and BN in this paper. AlN-BN composites were fabricated by hot-pressed sintering without additives. The relationship between the ratio of Al to BN and microstructure and...
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AlN was synthesized by in situ reaction with Al and BN in this paper. AlN-BN composites were fabricated by hot-pressed sintering without additives. The relationship between the ratio of Al to BN and microstructure and properties were studied. The results show that the content of AlN increases with the ratio of Al to BN increasing, and the density, hardness, bending strength, thermal conductivity and dielectric constant also increase with the ratio of Al to BN increasing. The results show that the samples with thermal conductivity 63.5 W/m·K and dielectric constant 8.76 are acquired by hot-pressed sintering under nitrogen atmosphere and two hours soaking time.
X-ray diffraction (XRD) analysis on different polished surfaces normal to the hot pressing direction reveals that the phase compositions of the polished surfaces from the outside to the inside are pure TiC, Ti_3AlC_2+...
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X-ray diffraction (XRD) analysis on different polished surfaces normal to the hot pressing direction reveals that the phase compositions of the polished surfaces from the outside to the inside are pure TiC, Ti_3AlC_2+TiC, pure Ti_3AlC_2 and Ti_2AlC+Ti_3AlC_2, no matter elemental powder or TiC is used as raw materials. It is found that ternary-layered carbide Ti_2AlC samples synthesized at 1500 ℃ by hot-pressing sintering are inhomogeneous and have a gradient *** probe X-ray micro-analysis (EPMA) indicates that the Al content along the hot pressing axis is parabolic, it is the highest in the center and the lowest at the both ends, while the Ti content is constant along the axis. The experimental result reveals that the evaporation of Al in samples in an open system during hot pressing sintering results in a gradient structure.
This research is that cellulose/poly-silicate hybrid material was prepared with viscose and poly-silicate by sol-gel method. The influence of aluminum salt and poly-silicate on hybrid material thermal property was stu...
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This research is that cellulose/poly-silicate hybrid material was prepared with viscose and poly-silicate by sol-gel method. The influence of aluminum salt and poly-silicate on hybrid material thermal property was studied. Based on the analysis of the DSC and TG curve of hybrid material, we have found that the hybrid material has splendid heat-resistance and fire retardancy.
Titanium diboride based composites, good candidates for contact materials, have high hardness, Young＇s modulus, high temperature stability, and excellent electrical, thermal conductivity. However a good interface of ...
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Titanium diboride based composites, good candidates for contact materials, have high hardness, Young＇s modulus, high temperature stability, and excellent electrical, thermal conductivity. However a good interface of TiB2/Cu is very difficult to achieve for oxidation of TiB2. To avoid this oxidation behavior, the in situ combusting synthesistechnology, SHS, was used to prepare TiB2/Cu composite. The characters of Ti-B-xCu SHS were studied in detail, such as combustion temperature, products phases and grain size. Based on the experimental results a proper technology way of self-high temperature synthesis plus quick press （SHS/QP） was determined and compact TiB2/Cu composites with relative density over than 97 pct of the theoretical were fabricated by this method. The properties and microstructures of these TiB2 based composites were also investigated.
This paper studies the temperature distribution of BN, an insulating material, sintered in the Spark Plasma Sintering ( SPS) system. The temperature distributions of BN at different heating rates were measured , which...
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This paper studies the temperature distribution of BN, an insulating material, sintered in the Spark Plasma Sintering ( SPS) system. The temperature distributions of BN at different heating rates were measured , which showed that seeking for an over high heating rate in SPS is not as desirable as controlling of a suitable heating rate in order to have a fast sintering with a uniform temperature distribution.
By using such flier-plate material,quasi-isentropic compression can be *** on it,hypervelocity launching is further *** a result,an extremely high dynamic pressure can be obtained in laboratory,offering a practical me...
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By using such flier-plate material,quasi-isentropic compression can be *** on it,hypervelocity launching is further *** a result,an extremely high dynamic pressure can be obtained in laboratory,offering a practical method for the comprehensive determination of materials behavior,response,equation-of-state and properties in dynamic loading process.
W-Mo system functionally graded material with density gradient, which can be applied to dynamic high-pressure technology, was prepared by hot-pressing at 1573K. In order to obtain fully dense body, suitable amount of ...
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W-Mo system functionally graded material with density gradient, which can be applied to dynamic high-pressure technology, was prepared by hot-pressing at 1573K. In order to obtain fully dense body, suitable amount of Ni and Cu was added. The FGM has quasi-continuous density variation in the thickness direction.
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