From the experimental data on ceramic/aluminum composite target, the mechanism of tungsten ball impacting a ceramic/aluminum composite target has been studied. By analyzing the transition of energy in the process of i...From the experimental data on ceramic/aluminum composite target, the mechanism of tungsten ball impacting a ceramic/aluminum composite target has been studied. By analyzing the transition of energy in the process of impact, a simple ballistic limit analytical model of tungsten ball impacting a ceramic/aluminum composite target has been proposed; and the result taken from this model is consistent with that of the experiment.展开更多
This article mainly deals with the preparation and properties of PZTthin films. A new type of Metal-Me tal Oxide composite target was developed. Relating factors have been discussed. The electrical and optical propert...This article mainly deals with the preparation and properties of PZTthin films. A new type of Metal-Me tal Oxide composite target was developed. Relating factors have been discussed. The electrical and optical properties of PZT thin films have also been studied.展开更多
Metallization of the ceramic surfaces of Si3N4 and Al2O3 was carried out in a composite diffusion coating vacuum furnace using a Ti-Cu composite target. The experimental process and influencing factors were discussed....Metallization of the ceramic surfaces of Si3N4 and Al2O3 was carried out in a composite diffusion coating vacuum furnace using a Ti-Cu composite target. The experimental process and influencing factors were discussed. Optical microscope （OM） , energy dispersive spectroscopy （EDS） , scanning electron microscopy （SEM） , X-ray diffusion （XRD） and sound emissive scratch test （SEST） were applied to evaluate the alloy layer formed on the ceramic surface. It was indicated that the diffusion coating alloy layer contained Cu, Ti, Fe, Al and Si etc. XRD result indicated that the diffusion coating alloy layer was composed of CuTi2, Cu, Si2 Ti and CuTi, Al2 TiO5 , Ti3O5. It was found that the diffusion coating alloy layer got bonded with ceramic well, and no spaUation occurred under the maximum load of 100 N. Deposited Si3N4 ceramic was welded with Q235 and the joining quality was examined. Robust joint was formed between Si3N4 ceramic/Q235. This present method has advantages in high efficiency and low cost and provides a new approach for producing ceramic and metal bond.展开更多
By using a ray method, a physical model that the backscattering of a tube is simplilied into reflection of a plane wave on layered media is suggested and reconstruction formulas of the parameters of a metallic tube co...By using a ray method, a physical model that the backscattering of a tube is simplilied into reflection of a plane wave on layered media is suggested and reconstruction formulas of the parameters of a metallic tube covered with sound-absorbing materials under the conditions of high frequency, fard field and thin tube are given. The internal and external radii of an aluminium tube filled by water or air and thickness of the covered material are reconstructed by using computer simulation and experimellts. The theoretical tesults obtained by this method are supported by experiments.展开更多
Polycrystalline Cr2AlC coatings were prepared on M38G superalloy using a two-step method consisting of magnetron sputtering from Cr-Al-C composite targets at room temperature and subsequent annealing at 620 ℃. Partic...Polycrystalline Cr2AlC coatings were prepared on M38G superalloy using a two-step method consisting of magnetron sputtering from Cr-Al-C composite targets at room temperature and subsequent annealing at 620 ℃. Particularly, various targets synthesized by hot pressing mixture of Cr, Al, and C powders at 650-1000 ℃ were used. It was found that regardless of the phase compositions and density of the com- posite targets, when the molar ratio of Cr：Al：C in the starting materials was 2：1：1, phase-pure crystalline Cr2AlC coatings were prepared by magnetron sputtering and post crystallization. The Cr2AIC coatings were dense and crack-free and had a duplex structure. The adhesion strength of the coating deposited on M38G superalloy from the 800 ℃ hot-pressed target and then annealed at 620 ℃ for 20 h in Ar exceeded 82 ± 6 MPa, while its hardness was 12 ± 3 GPa.展开更多
The search is now on for new materials that can be used for ionic stripping. Materials that maximize the stripping of the structural ion are important for conducting experiments with quark-gluon plasma. Although this ...The search is now on for new materials that can be used for ionic stripping. Materials that maximize the stripping of the structural ion are important for conducting experiments with quark-gluon plasma. Although this paper is a theoretical study, it offers practical applications, in heavy-ion accelerators, of the new effect of collision multiplicity with high-energy ions interacting with polyatomic targets. It is shown that internal nanostructured targets in which the collision multiplicity effect is manifested can more efficiently strip out structural ions compared to standard internal targets for stripping. A target consisting of oriented nano-tubes with the C_（240） chirality（10,0）is considered as an example. A comparison with the stripping process on a carbon target with the same number of misaligned atoms in a unit of volume C is provided.展开更多
文摘From the experimental data on ceramic/aluminum composite target, the mechanism of tungsten ball impacting a ceramic/aluminum composite target has been studied. By analyzing the transition of energy in the process of impact, a simple ballistic limit analytical model of tungsten ball impacting a ceramic/aluminum composite target has been proposed; and the result taken from this model is consistent with that of the experiment.
文摘This article mainly deals with the preparation and properties of PZTthin films. A new type of Metal-Me tal Oxide composite target was developed. Relating factors have been discussed. The electrical and optical properties of PZT thin films have also been studied.
文摘Metallization of the ceramic surfaces of Si3N4 and Al2O3 was carried out in a composite diffusion coating vacuum furnace using a Ti-Cu composite target. The experimental process and influencing factors were discussed. Optical microscope （OM） , energy dispersive spectroscopy （EDS） , scanning electron microscopy （SEM） , X-ray diffusion （XRD） and sound emissive scratch test （SEST） were applied to evaluate the alloy layer formed on the ceramic surface. It was indicated that the diffusion coating alloy layer contained Cu, Ti, Fe, Al and Si etc. XRD result indicated that the diffusion coating alloy layer was composed of CuTi2, Cu, Si2 Ti and CuTi, Al2 TiO5 , Ti3O5. It was found that the diffusion coating alloy layer got bonded with ceramic well, and no spaUation occurred under the maximum load of 100 N. Deposited Si3N4 ceramic was welded with Q235 and the joining quality was examined. Robust joint was formed between Si3N4 ceramic/Q235. This present method has advantages in high efficiency and low cost and provides a new approach for producing ceramic and metal bond.
文摘By using a ray method, a physical model that the backscattering of a tube is simplilied into reflection of a plane wave on layered media is suggested and reconstruction formulas of the parameters of a metallic tube covered with sound-absorbing materials under the conditions of high frequency, fard field and thin tube are given. The internal and external radii of an aluminium tube filled by water or air and thickness of the covered material are reconstructed by using computer simulation and experimellts. The theoretical tesults obtained by this method are supported by experiments.
基金supported by the National Natural Science Foundation of China under Grant Nos.51271191,51571205 and 51401209
文摘Polycrystalline Cr2AlC coatings were prepared on M38G superalloy using a two-step method consisting of magnetron sputtering from Cr-Al-C composite targets at room temperature and subsequent annealing at 620 ℃. Particularly, various targets synthesized by hot pressing mixture of Cr, Al, and C powders at 650-1000 ℃ were used. It was found that regardless of the phase compositions and density of the com- posite targets, when the molar ratio of Cr：Al：C in the starting materials was 2：1：1, phase-pure crystalline Cr2AlC coatings were prepared by magnetron sputtering and post crystallization. The Cr2AIC coatings were dense and crack-free and had a duplex structure. The adhesion strength of the coating deposited on M38G superalloy from the 800 ℃ hot-pressed target and then annealed at 620 ℃ for 20 h in Ar exceeded 82 ± 6 MPa, while its hardness was 12 ± 3 GPa.
文摘The search is now on for new materials that can be used for ionic stripping. Materials that maximize the stripping of the structural ion are important for conducting experiments with quark-gluon plasma. Although this paper is a theoretical study, it offers practical applications, in heavy-ion accelerators, of the new effect of collision multiplicity with high-energy ions interacting with polyatomic targets. It is shown that internal nanostructured targets in which the collision multiplicity effect is manifested can more efficiently strip out structural ions compared to standard internal targets for stripping. A target consisting of oriented nano-tubes with the C_（240） chirality（10,0）is considered as an example. A comparison with the stripping process on a carbon target with the same number of misaligned atoms in a unit of volume C is provided.
