Advanced Materials Research Vol. 1052

Abstract: In this Paper an original 800MPa cold rolled dual phase steel with low carbon and high silicon as well as some amount of Mn had been investigated in lab. The study shows that the microstructures of the steel mainly consist of ferrite, along with martensite with the content of 20%~25% which distributes homogenously on the ferrite grain boundary. The grain size of the ferrite is homogenous and with the grade of 13-14. The characteristics of the microstructure results in the excellent mechanical properties of the steel with Rp0.2=485~515MPa,tensile strength Rm=795~805MPa,total elongation A80mm=18%~19.5%,and n=0.135-0.145.

Abstract: C_f/ZrC-xCu composite ceramics with different Cu content were prepared by self-propagating high-temperature synthesis/pseudo–hot isostatic pressing (SHS/PHIP). The effect of Cu content on the microstructure and properties of C_f/ZrC composite ceramics were investigated. Our results indicated that carbon fiber was serious chemical damaged in the absent of Cu, accompanied by attenuating of the reinforced effect.Whereas, the density of the complex was increased in the present of Cu content in a dose-dependent-way due to the better fluidity of Cu. Adding to Cu into the complex material leads to the increased diffusion resistance of the elements, decreased damage of the carbon fiber. Meanwhile, the ability of flexural strength manifested as incureasing-decreasing manners according to the elevation of Cu content, while, the fracture toughness was increased gradually. We finally concluded that we could get the best composite ceramic in the present of 25V% of Cu.

Abstract: Brush plating has been an important technology for the mending of the scratched surface of the engineering parts in recent years. The process for brush plating mending of deeply scratched surface of the parts made by 7A04 super-duralumin alloy is introduced in this article. The merits of the brush plating mending technology of 7A04 super-duralumin alloy are discussed.

Abstract: To overcome poor mechanical properties of polyurethane, carboxylated cellulose nanospheres were incorporated into polyurethane in an organic polar solvent, dimethylformamide to prepare the nanocomposite films. Morphological, structural, mechanical and thermal characterization of the nanocomposites was done with scanning electron microscopy, Fourier transform infrared spectrometry, micro–control electronic universal testing machine and thermal gravimetric analysis. The critical challenge to achieve high macroscale properties of the bulk nanocomposites is the ability to obtain well–dispersed cellulose nanospheres in polymer matrices.

Abstract: Cadmium ion doping was carried out during electrochemically cathodic plating nickel hydroxide on platinum films coated n-silicon (Pt/n-n⁺-Si electrode) in 0.1 M nickel nitrate solution containing 0.035 M cadmium nitrate. The morphology and composition of the products were characterized by scanning electron microscope (SEM) and x-ray photoelectron spectroscopy (XPS), respectively. A two-electrode cell based on Cd-doped NiO/Pt/n-n⁺-Si electrode and a platinum counter has been used for determination of hydrogen peroxide in absence of reference electrode by photocurrent measurement at a zero bias. The emphasis is laid on that the cadmium doping remarkably improves the sensibility of the photoelectrochemical hydrogen peroxide sensor. Under optimizing conditions a sensitivity of 254.6 μA mM^-1 cm^-2 and a linear response range from 0.02 mM up to 0.12 mM with a determination limit of 2.0 μM were achieved in a potassium hydroxide (KOH) solution at pH =13.3.

Abstract: The paper provides a novel method for co-simulating 1-3 piezocomposites performance. Both equivalent parameter model (EPM) and finite element mode (FEM) are utilized in the method, and a co-simulation software is developed based on the method. The performance of 1-3 piezocomposite can be conveniently calculated by the software. Therefore the method and software involved in this research can be applied to the design of 1-3 piezocomposite.

Abstract: This article mainly introduced the preparation and properties of the thermal seed composite. And multiple groups of experiments have been done, which controlled by different content of carbon nanotubes, different surfactants. The results showed that: Fe₃O₄/CNTs can be made through chemical co-precipitation. Using the same surfactant and under the same experimental conditions, the carbon nanotubes’ surface coating is best and most homogeneous, when the content of the carbon nanotubes is 12.5%. When the content of carbon nanotubes is 12.5% and the experimental conditions are same, choosing CTAB as the surfactant, rather than SDS, finally get the better performance of sample. So the optimal parameters for the experiment are that the content of CNTs is 12.5%, and the choice of surfactant is CTAB. At this time, the surface of carbon nanotubes coats uniformly and the magnetic properties meet the requirements of tumor hyperthermia. In addition, as the carbon nanotubes contain varying degrees of nanocarbon particles, graphite fragments, amorphous carbon and other impurities, Therefore, in this paper, the carbon nanotubes are carbon nanotubes which have been purified with concentrated nitric acid.

Abstract: A phase field model of three-phase composite ceramic tool materials with two kinds of nanoparticles is set up in this research. The three-dimensional simulation algorithm is modified and a new efficient algorithm is established. The microstructure evolution of three-phase nanoceramic tool materials is more efficiently and successfully simulated in 200x200x200 unit size. Microstructure evolution of single-phase and three-phase ceramic tool materials is simulated respectively. It can be found that the peak value of grain size distribution for three-phase nanoceramic tool material is smaller than average diameter. It indicates that the nanoparticles not only restrain grain boundary migration, but also prevent the elimination of small grains and refine matrix grains.

Abstract: Composite coatings of PTFE/PEEK (Polytetrafluoroethylene/Polyetheretherketone) were prepared by electrostatic powder spraying method. The factors were investigated on the preheating temperature and working temperature by the orthogonal experimental method. The results show that 250°C preheating temperature and 100°C working temperature are better conditions for playing good performance of PTFE/PEEK coatings.

Abstract: nanosilica porous thermal insulating composites belong to super thermal insulations, which are prepared by dry molding technology. They have many advantages in comparison with aerogel such as easy preparation and good mechanical property. However, springback phenomenon is found in the process of molding. The springback is easy to lead to cracking of the samples, which directly affects applications of the composites. In order to solve this problem, steam curing method is introduced and the effects of steam curing medium and steam curing time on springback ratio are investigated. The results show that the springback ratio of composites is only 6.45% when water is selected as steam curing medium and the optimum steam curing time is 30 min.