Applied Mechanics and Materials Vols. 395-396

Abstract: SiC particle reinforced AlCu5Mn composite foams (SiCp/ZAlCu5Mn composite foams) were fabricated by the direct foaming of the melt. The quasi-static compressive properties of SiCp/ZAlCu5Mn composite foams were tested by compressive test. The effects of SiC particle, the average diameter of pores, and the relative density on the quasi-static compressive properties of SiCp/ZAlCu5Mn composite foams were performed with the universal material testing machine. The microstructure of SiCp/ZAlCu5Mn composite was studied by SEM. The results show that choosing small size of SiC particles as reinforced material, thinning pore diameter, and increasing the relative density of SiCp/ZAlCu5Mn composite foams with the same volume fraction of SiC particles can improve the energy absorption ability under the quasi-static loading. SiCp/ZAlCu5Mn composite foams are of well compressive property. The compressive deformation course of SiCp/ZAlCu5Mn composite foams involves three stages that are the linearly elastic deformation region, the collapse plateau region, and the densification region. The test results may be influenced by strain gauge, data processing method, shape of incident wave etc.

Abstract: Oil shale is a very important alternative energy, hydraulic mining is an effective method for oil shale utilization in Jilin Province. For the Nong'an oil shale in Jilin Province, the average compressive strength of horizontal bedding is 17.14MPa, and the average compressive strength of vertical bedding is 10.90MPa. For cone straight-shaped nozzle, when the jet pressure P is 10MPa and the nozzle outlet diameter d is 1mm, striking force generated by the jet is 15.65N, it can break the oil shale.

Abstract: The coke reactivity is one of the major evaluation indexes of coke. But there is still no clear statement on the reaction temperature as well as the way of reaction. In order to have a further understanding on the process of coke solution loss reaction in the blast furnace, the present paper studied the coke reactivity at different temperatures and finally found out the reaction rules and constraints in different zones of the blast furnace.

Abstract: Biocomposite scaffolds of poly (lactic-co-glycolic acid) (PLGA), multiwalled carbon nanotubes (MWNTs), and hydroxyapatite (HA) nanoparticles were fabricated by gas-foaming and particle-leaching technique. The structure, surface morphology, and some properties of these PLGA/MWNTs/HA composites were evaluated. MWNTs and HA were evenly scattered in the scaffolds. The porosity of scaffols were decreased when the content of MWNTs increased to 1wt%. The mechanical strength of scaffols can be strengthened by the the addition of 1wt% MWNTs. The PLGA/MWNTs/HA biocomposite scaffolds have the great potential application in bone tissue regeneration.

Abstract: Undoped and Fe-doped (Fe ions content was 0.1) TiO₂ thin film prepared by Sol-gel method. X-ray diffraction (XRD) results showed that TiO₂ gel annealed at 500°C was crystallized anatase phase. The contact angle for undoped and Fe-doped TiO₂ thin film was 47.1° and 8.8°. The transparent spectra showed that the cutoff wavelength of was red shift. The band-gap of Fe-doped TiO₂ film was 3.47 eV.

Abstract: The problem of UHMWPE laminated fiber plate resisted projectile was studied by the non-linear FEM that Truegrid/LS-Dyna. The material parameters of fiber layers were gained after synthesizing test datum and some references, then the model of *MAT_COMPOSITE_DAMAGE was used to simulate the UHMWPE laminated fiber plate. The results of numerical simulation were compared with the test results, and the method of numerical simulation in the paper was proved.

Abstract: A novel polyimide (PI) films with three kinds of monomers was synthesized in this paper. The polyimide unit is derived from Pyromellitic dianhydride (PMDA), 3,3',4,4'-benzophenonetetracarboxylic dianhydride, (BTDA), and 4,4, -diaminodiphenyl ether (ODA). The dielectric properties of the films were measured. The dielectric spectra show that dielectric constant is about 3.7, which is larger than the PI with two kinds of monomers. In addition, the loss tangent and conductivity of the films is quite small, which is important for the practical use of them.

Abstract: Ce:Mn:LiNbO₃ single crystals with different [L/[N were used for the measurement of Raman spectrum. Each peak appeared in the Raman spectrum was ascribed to the basic vibration modes of the LiNbO₃ crystal according to the basic analysis and the achievements obtained by the earlier researches. The results showed that the peak width at half height (FWHM) of the A₁(TO₁) vibration mode become wide gradually with the increase of the [L/[N. However, the FWHM of A₁(TO₂) and A₁(TO₄) vibration mode decrease with the increase of the [L/[N in the crystal. The FWHM of the E(TO₁) vibration mode was decrease with the increase of [L/[N in the crystal, and also the linear relationship between the FWHM of the E(TO₁) vibration mode and the [L/[N in the crystal. According to the relationship between the [L/[N in the crystal and the FWHM of the E(TO₁) vibration mode for the pure LiNbO₃ crystal, the quantitative relation for the Ce/Mn co-doped LiNbO₃ crystal was revealed by amending the empirical formula for pure LiNbO₃ crystal on the basis of the results measured by ICP-AES. The quantitative relation of the FWHM of the E(TO₁) vibration mode and the [L/[N was given by the Polynomial Fit of the experimental data.

Abstract: A new kind of the electromagnetic shielding composite coatings with high performance was prepared using the Ni-Cu-coated glass fibers and nickel powders as fillers and using epoxy resin as binder. The effects of the fibers on the conductivity and electromagnetic shielding effectiveness of the coatings were studied. The study results show as follows: 1) when the optimum ratio of the fillers to epoxy resin is 4:1, the coatings containing 6 wt% the Ni-Cu-coated glass fibers has best conductivity and electromagnetic shielding effectiveness; when the coating layer thickness is 300 μm, the shielding effectiveness of the coatings is up to 43.71-52.31 dB and increased an average of 13.94 dB compared with the nickel powders/ epoxy resin electromagnetic shielding coatings in the frequency range of 0.3-1000 MHz. This offers a new idea to enhance the added value of the glass fibers and the prevention of electromagnetic environmental pollution.