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The excessive residual stress induced by quenching in steels will easily result in distortion and failure of parts. In order to obtain the more suitable quenchant, quenching process of Cr12MoV steel with different mediums involving water and oil are simulated, respectively. In present paper, the influence of nonlinear surface heat transfer coefficient, thermodynamic parameters and latent heat are considered comprehensively. The distribution of temperature, microstructure, hardness and residual stress after quenching for Cr12MoV steel are simulated by DEFORM finite element software. According to the results mentioned above, the variations of each field of the steel are analyzed.

This paper presents a new method which combines the fuzzy theory with the traditional PI control to obtain the accurate tracking of the compensating current of the active power filter (APF) in full frequency range. Online adjustment of the parameters of the controller is realized by using fuzzy reasoning and defuzzication, so as to achieve the accurate tracking of the compensating current and thereby improve the capabilities of the APF to suppress the harmonics effectively. Simulation analysis and experiment results verify the effectiveness of the presented method.

Nano agnesium phosphate (n-MP) was synthesized using a chemical precipitation method. The results revealed that the synthesized n-MP with the mean particle size of 79 nm and could be degradable in PBS solution with the weight loss was 70.4w% after soaking for 60 days. The extracts of n-MP caused no cytotoxicity on L929 cells, revealing good biocompatibility, which satisfied the relevant criterion on biomaterials.

When the sheet metal is curled into the pipe, springback always makes it in poor roundness. Experiments show that the process parameters can influence the springback value. So in this paper it took series of researches to find the regularity of process parameters influence the curling springback. In this paper it designed one set of curling mould, and chose the punch force, material properties, blank thickness and friction condition as the subject studied separately. After experiments it obtained the influence regularity, and then it took an analysis on the phenomenon in this paper. The results will be helpful to decrease the springback value in curling process.

When building the radial basis function (RBF) neural network with traditional method, the property of the network is easily influenced by the distribution of training samples. The learning ability and generalization ability are hard to achieve the optimum. In this paper, it presents a new method to solve this problem. In the method it replaced the traditional clustering algorithms with genetic algorithms to optimize the distribution of RBF. At the same time it combined the steepest descent method with GA to solve the binary defect of GA encoding. After experiments the results showed that the constructed neural network has a better architecture and more accuracy than that built with traditional method.

Since CuInSe2 (commonly called as CIS) materials has become one of most important photovoltaic materials, they are investigated with optical spectroscopies in this paper. The crystal structure, surface microstructure morphology and composition of the samples are analyzed in XRD and SEM with EDX, and the surface electronic state and optical properties of the samples are characterized in X-ray photoelectron spectroscopy (XPS) and Ultraviolet-visible Spectrum instruments. The results show that CIS phase is very uniform, some impurity phases appear in the samples， the atomic distributing percentages of the surfaces of bulk samples are very consistent in the composition ratio forming the crystal phases of the samples, and the atomic electrons are more active than ones in the relevant elements. Furthermore, the thin film of the sample has high solar energy absorptivity, and is suitable for to be manufactured as solar cell.

This research focused on the numerical simulation of electric field tuning characteristics of the magnetoelectric microwave devices with the core of the laminated ferrite-piezoelectric magnetoelectric materials. Firstly, we proposed an expression for the shift of ferromagnetic resonance (FMR) frequency tuning by external electric field in piezoelectric layer, then substituted the expression of magnetoelectic (ME) constant into this expression, which can convert the electric field tuning on the laminated magnetoelectric materials into the equivalent magnetic field tuning on the ferrite layer. Secondly, we built a numerical analysis model for tunable magnetoelectric microwave device which is formed by the laminated magnetoelectric material and microstrip line, and put the equivalent magnetic field into this numerical model, then the numerical analysis model of novel tunable magentoelectric microwave device is completed. Taking a tunable ME microwave resonator for example, the S parameters calculated by the numerical model in this paper are in good agreement with experimental results both qualitatively and quantitatively. Considering the demand for the designing and applying of the microwave devices, we studied the effect of geometrical dimensions of the ferrite layer (YIG/GGG) on the return loss and the resonance frequency.

In this paper, application of drawbead optimization using FEM simulation and neural network was discussed for the drawing of car door. A neural network model was established to simulate the nonlinear mapping relation between the drawbead force and sheet forming parameters. The samples needed for training and testing were obtained by FEM simulation. Once the ANN trained successfully, the drawbead optimized design could be realized by using the ANN.

Water jet cavitation peening is applied to improve the strength and mechanical properties of the friction-welded joints of titanium alloys. Scanning electron microscopy observations of the microstructure of the welded joints and welded area before/after water jet cavitation peening confirm slip dislocation at the microstructure near the surface of the specimens. The residual stress on the surface of the welded joint is measured by X-ray diffraction. The results indicate the effect of peening time on the strength of compressive residual stress.

This paper focuses on the thermal stress and deformation analysis of the support plate of a nuclear reactor during the quenching process. A 3D finite element model of the support plate is incorporated into nonlinear coupling analysis that considers temperature, stress, and deformation. To verify the effect of cooling rate on the thermal stress and deformation of the model, we applied the heat transfer coefficients of water and heat treatment oil, depending on temperature variations, into heat conduction analysis. This analytical method enables the determination of the maximum deformation and residual stresses, so that the strength of the support plate can be identified.