Key Engineering Materials Vols. 575-576

Abstract: In this paper, the ZnO/Cu₂S/ZnO complex films were fabricated by Radio Frequency (RF) magnetron sputtering, and their transparent, conductive and photocatalytic properties have been investigated. The results show the properties of ZnO/Cu₂S/ZnO complex films vary when the top layer ZnO thickness changes.

Abstract: one-dimensional SrFe_11.85Sm_0.15O₁₉ nanofibers were synthesized by electrospinning combined with heating treatments. This paper involved an investigation of how heat treatment temperature and Sm³⁺ influence structure and morphology of nanofibers. FTIR and XRD results demonstrated that SrFe_11.85Sm_0.15O₁₉ magnetoplumbite phase was formed with increasing of calcined temperature, and small amountα-Fe₂O₃ and SmFeO₃ were detected at low temperature and high temperature, respectively. The calcined temperature had a great impact on the morphology of nanofibers, which changes from a continuous fibrous structure to large plate grain. The VSM results revealed that the Ms and Hc of nanofiber were both increased with calcined temperature.

Abstract: The paper studied the influences of some industry wastes on the properties of composite Portland cement. Different amount of wastes were added as cement mixture. Through the investigation of properties of cement by orthogonal experiments, the optimum combination was obtained. The hydration products were analyzed by XRD and SEM. Its hydration mechanism was investigated and the result shows that with appropriate ration of each influencing factors, the cement could meet the national standard 42.5MPa of cement strength.

Abstract: The paper studied that the activity, hydraulicity and Alkali Activation of ferroalloy slag compared to granulated ground blast furnace slag, and a further discussion was carried on ferroalloy slag used as addition of cement. The result shows that the activity index meet national standard and has a well Hydraulicity. Moreover,Ca(OH)₂ has a great activition to ferroalloy slag.

Abstract: It is a worldwide difficulty to preserve earth monument in wet area. To solve this problem, professor Zhou Shuanglin, an expert of earth monument preserving with College of Archaeology and Museum, Peking University, developed a consolidation agent named acrylic non-aqueous dispersion. But the study on this consolidation agent is still in its initial stage at present for most of its experimental researches are limited to northwest china and no research reports aimed at wet area in southwest China were found so far. To check out the efficiency of this consolidation agent in wet area, southwest China, a consolidating experiment was conducted by applying this consolidation agent to soil samples from kiln Qionglai earthen monuments located in outskirt of Chengdu city, the capital of Sichuan province. In this experiment, the changes of weight, permeating speed and short-term water resistance of specimens after consolidating were investigated and compared with those for northwest area. The study shows that acrylic non-aqueous dispersion consolidation agent developed by professor Zhou Shuanglin is also effective to a certain degree for the earth monument in wet area, southwest China.

Abstract: In some fields, the rigid prismatic pairs have been gradually replaced by some flexible prismatic pairs. It is described a new type flexible prismatic pair in this paper. Its material is 65Mn spring steel. It is applied to the high frequency vibration field for its elasticity and structural advantages. The prismatic pair is based on a one-way four-bar linkage, which is consisted of some bent plate structures. Firstly its model is designed. Secondly the width error, the incision arc error and some other errors are analyzed in details. Based on the Paros J stiffness calculation formula and the Smith ST error analysis method, its relative stiffness error model is established. Finally by using finite element method, a simulation of deformation is made in the actual working conditions. And the error model is correct.

Abstract: For the purpose of high-efficiency recovery and utilization of steel slag in cement and concrete, a comparative research on the cementitious property of several kinds of steel slag in six different cementitious systems have been carried out. The results show that the changes of cementitious systems and the basicity of steel slag have no significant effect on the mortar fluidity. The cooperating use of steel slag and ground granulated blast furnace slag is helpful to activate the cementitious property of steel slag. The basicity of steel slag can generally reflect the long-term cementitious properties of steel slag.

Abstract: This paper designs a platform which is used for material pose alignment of complex curved surface parts laser processing. The parallel platform is based on a hybrid mechanism with five spatial degrees of freedom. The mechanism is built up by three parallel vertical chains {(P-R-C), (C-R-C-R), (P-H)} and two series single opened chains {(P), (P)}. This processing platform is an ideal hybrid platform with 2R-3T, and it has the advantages of both the parallel mechanism and the series mechanism. The DOF (degree of freedom) of the parallel mechanism is calculated and the positions of the moving platform are analyzed. The results of the position-equations are simulated by using ADAMS software. It is shown that the processing platform is able to meet the requirements of any angle positions of various materials processing, and realize material special machining.

Abstract: The Al₂TiO₅ Coating was deposited on Ti-6Al-4V alloy substrate by homemade micro-arc oxidation system. The microstructure of Ti-6Al-4V titanium alloy, the phase of coating, the bonding force of the coating and matrix, sulfuric acid corrosion resistance and high-temperature oxidation resistance were study by inverted microscope model, Xray diffract meter, scanning electron microscopy, the coating adhesion automatic scratch tester, box-type furnace. The results show that the phase of coating is composed of Al₂TiO₅ and Al₂SiO₅, and Al₂TiO₅ .is the main component, the coating surface consists of discharging pit and flange which are unequal in size, rough and overlap and micro-arc oxidation pit diameter increases with the voltage. When micro-arc oxidation voltage is constant, the longer micro-arc oxidation time, the greater the Ti-6Al-4V alloy coating and the substrate binding force. The corrosion resistance of Ti-6Al-4V alloy was improved in sulfuric acid due to micro-arc oxidation; the sulfuric acid corrosion resistance of the coated samples was improved 11 times when the micro-arc oxidation time increased from 5min to 60min. the high-temperature oxidation resistance of Ti-6Al-4V alloy with micro-arc oxidation coatings is higher than Ti-6Al-4V alloy without micro-arc oxidation coating.

Abstract: The temperature history of HPC remarkably affects their volume stability and mechanical properties, but no enough attention is pay to it in the literature. In this paper, for the purpose of clarifying the temperature effect of above-mentioned behaviors, a series of tests on autogenous deformation, compressive strength and elastic modulus of HPC are carried out. The outcome of research as follows: surrounding temperature intensely influences autogenous strain and mechanical indices; elevated temperature not only results in increased shrinkage strain, compressive strength and elastic modulus, but also accelerates their rates of development.