In this work, Fe and Si powders were used to fabricate 6.5% Si silicon steel. The mixing powder was rolled into strip and then treated at 900°C in Ar. Sn was added into the mixing powder to investigate the effect...
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In this work, Fe and Si powders were used to fabricate 6.5% Si silicon steel. The mixing powder was rolled into strip and then treated at 900°C in Ar. Sn was added into the mixing powder to investigate the effect of Sn on the sintering. The density, composition, and structure were examined. The results show that Fe almost does not react with Si at 900°C But with the addition of Sn, Fe reacts with Si to produce Fe3Si at 900°C Increasing the amount of Sn accelerates this reaction. When the amount of Sn addition is excessive, there will leave many pores in the alloy because the reaction rate is too fast to shrink. The proper amount of Sn addition can decrease the sintering temperature and shorten the sintering time.
Polycrystalline alumina was prepared at high temperature and high pressure from combustion reaction plus mechanical pressure. The defect structure in the sintered alumina was investigated by transmission electron micr...
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Polycrystalline alumina was prepared at high temperature and high pressure from combustion reaction plus mechanical pressure. The defect structure in the sintered alumina was investigated by transmission electron microscopy and a regular hexagonal dislocation network was found. Diffraction contrast technique revealed that the regular hexagonal network on the (0001) plane was composed of three dislocations with Burgers vectors: 1/3[12¯10], 1/3[2¯110] and 1/3[112¯0]. The formation process of dislocation network was discussed.
To reuse roller waste as a raw material of high performance green ceramic balls,three kinds of white alumina ceramic balls whose wear resistance were 2-3 times of the best high alumina ceramic ball with90% Al2O3 were ...
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To reuse roller waste as a raw material of high performance green ceramic balls,three kinds of white alumina ceramic balls whose wear resistance were 2-3 times of the best high alumina ceramic ball with90% Al2O3 were prepared,and the Al2O3 content of the prepared balls was 75%.It is found that the effect of calcia and magnesia on the wear resistance of ceramic balls is contrast to the accepted one: the wear rate of the ceramic balls prepared in CaO-Al2O3-SiO2 system is the lowest and the wear rate of the ceramic balls prepared in MgO-Al2O3-SiO2 is the *** main crystal phase of the ceramic ball is mullite and *** ceramic ball granular is uniform and fine with 4-5 um average *** pore diameter is about 2 *** wear way of the ceramic balls is mainly transcrystalline fracture.
This paper discusses the present status of, and future perspectives on nano Traditional Chinese medicine (TCM) by describing the concept, its methodologies, preservation, drug effect and pharmacological study. The exp...
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Pulse current heating technology is used to join TiB2-Ni cermets with Ti6A14V at different temperatures (1023K, 1073K and 1123K) with 7MPa pressure and Cu foil and Ni foil are used as joining interlayer. Joint points ...
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Pulse current heating technology is used to join TiB2-Ni cermets with Ti6A14V at different temperatures (1023K, 1073K and 1123K) with 7MPa pressure and Cu foil and Ni foil are used as joining interlayer. Joint points increase with welding temperature. The microstructure of joints is observed through SEM images and micrographs. The diffusion coefficient (D0) of Cu at the Cu/TiB2 interface is calculated by the EPMA patterns. The diffusion principle of pulse current heating and influences of electric field and current on atom diffusion are studied.
Using a reticulated polyurethane sponge with interconnected pores as primal framework and immersing into TiB2 slurry consisting of Ni and Mo as sintering additives, a porous TiB2 ceramics with high porosity and interc...
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Using a reticulated polyurethane sponge with interconnected pores as primal framework and immersing into TiB2 slurry consisting of Ni and Mo as sintering additives, a porous TiB2 ceramics with high porosity and interconnected pores was prepared by immersing and high temperature sintering process. The rheology of TiB2slurry which used silica sol as a binder was studied. The optimum condition of the slurry suitable for impregnating the polyurethane sponge was obtained. The flexural strength of the porous reticulated TiB2 ceramics can reach 1 MPa.
In this paper, silicon nitride (Si3N4) ceramics by aligning α-Si3N4 whiskers were prepared via tape casting, hot-press sintering technique using Y2O3 and MgO as sintering additives. Aligned α-Si3N4 whiskers were rea...
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In this paper, silicon nitride (Si3N4) ceramics by aligning α-Si3N4 whiskers were prepared via tape casting, hot-press sintering technique using Y2O3 and MgO as sintering additives. Aligned α-Si3N4 whiskers were realized by modifying the tape casting technique. After tape casting, Si3N4 tape with good flexibility and uniform pores can be obtained. Microstructures of the tape, green body and sintered sample were observed by SEM images. The results show α-Si3N4 whiskers in Si3N4 tape and green body were aligned preferentially along the tape casting direction. Si3N4 ceramics with aligned elongated grains are developed by hot-press sintering technique based on the reaction between Si3N4 and the sintering additives which lead to the liquid phase.
A new kind of functionally graded materials (FGM) with density gradient has come to show great potentials as flier-plates for creating quasi-isotropic compression waves. In order to meet the demand of lower density in...
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A new kind of functionally graded materials (FGM) with density gradient has come to show great potentials as flier-plates for creating quasi-isotropic compression waves. In order to meet the demand of lower density in the front face and wider density range for such flier-plate, Mg with a density of 1.74g/cm3 and W of 19.3g/cm3 are selected to make Mg-W system density graded materials, Mg-W alloys with various mass fractions of Mg and W were sintered by spark plasma sintering (SPS) technique at low temperatures, and the processing of densification is mainly investigated. It is found that, up to 92wt%W, the Mg-W alloys can be fully densified at 873K due to the conglutination of Mg particles. The Mg-W alloys still exist as a mechanical mixture of Mg and W. Finally, the Mg-W density graded materials with a density change from 1.74g/cm3 to 10.55g/cm3 have been successfully prepared.
In the present study, BaTi2O5 thin films were epitaxially grown on MgO (100) substrate by pulsed laser deposition, and the microstructure of the films was investigated. The b-axis oriented BaTi 2O5 thin film was obtai...
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ISBN:
(纸本)9788880800842
In the present study, BaTi2O5 thin films were epitaxially grown on MgO (100) substrate by pulsed laser deposition, and the microstructure of the films was investigated. The b-axis oriented BaTi 2O5 thin film was obtained at the optimum substrate temperature (Tsub = 973 K) and oxygen partial pressure (PO2 = 12.5 Pa). The as-deposited film was epitaxially grown on MgO (100), exhibiting a dense and rectangularly crossed granular texture. The epitaxial relationship between the film and substrate was BaTi2O5 (020) [100] // MgO (100) [001] and BaTi2O5 (020) [100] // MgO (100) [010].
In this study, K3Li2-xNb5+xO 15+2x (KLN) thin films were prepared by laser-ablated a sintered ceramic target. For an optimum deposition condition, in-situ post annealing method was employed on as-deposited films. XRD ...
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In this study, K3Li2-xNb5+xO 15+2x (KLN) thin films were prepared by laser-ablated a sintered ceramic target. For an optimum deposition condition, in-situ post annealing method was employed on as-deposited films. XRD measurements showed that KLN films with (310) preferred orientation were obtained on fused quartz substrate. Surface morphology studies indicated mat in-situ post annealing could improve the surface quality of KLN thin films. The average transmittance of as-deposited and annealed films in the visible range was nearly 80% to 90%.
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