Applied Mechanics and Materials Vols. 644-650

Abstract: The Gleeble3500 combined with SEM, TEM and other experimental methods are employed in this paper to investigate the effects of zirconium content on impact toughness of heat affected zone (HAZ) of hull structure steel plate during the large heat input welding. The results showed when 0.01% zirconium were added in the steel, the impact energy reached 224 J at-60°C experienced 150 kJ/cm welding heat input. But the large-size rectangular inclusions are found in CGHAZ when 0.02% zirconium were added in the steel, the impact energy fell to 38 J at-60°C experienced 150 kJ/cm welding heat input, the large-size inclusions, especially rectangular inclusion, were the main cause for the sharp decline of low temperature toughness after welding.

Abstract: If the pressure sensitive adhesive is coated on the back, it can be used for bonding electronic tag, overburden, protective layer, and RFID layer. The acrylate pressure sensitive adhesives are simple and less pollution, so more and more companies pay attention on this kind of binder. Since the thickness of adhesive layer is relatively small, ink-jet printing is now widely used to easily obtain thin layer and design the pressure sensitive adhesive shape of different parts. So how to get superior performance pressure sensitive adhesive which is suitable for ink-jet printing become an urgent problem in printed electronics. The experiment was conducted through solution copolymerization of various vinyl monomers which were selected on the principle of solvent parameter prepared by free radical polymerization. The monomer, initiator mixture solution was dropped in continuous and synchronization process. By regulating the amount of initiator and polymerization temperature, we could effectively reduce the system viscosity and prepare high quality high-solids acrylate UV-curable pressure sensitive adhesives with low viscosity for ink-jet printing. The influence of initiator, solvents, transfer reagents and temperature on the structure and properties of the resin were discussed.

Abstract: Satellite oilfield is in high water cut production period, many reservoirs flooded, or great changes after long-term water injection pore structure, heterogeneity is more serious. These strata to high-dose slug of deep processing, plugging agent dosage, only cheap oil displacement system has use value. Therefore, urgent need to develop a economic and effective system of new type displacement, especially for high permeability, high permeability and deep processing of large hole formation. A grade sodium soil clay particle displacement agent used with HJ - 708 can enhance the blocking effect, and can prevent or reduce the particle migration. This article by viscosimetry screening reagents with clay particles oil displacement agent and the added amount and the kinds of grade A sodium plus the amount of soil to optimize indoor experiment and A series of oil displacement system for optimization and evaluation. High pressure model of indoor experiments show that the new type of oil displacement system blocking rate reached more than 90%, on the basis of the original recovery efficiency increased by seven percent.

Abstract: The paper introduces the structure and basic theory of the intrinsic safety explosion-proof, the parameters of each part and the principles of selection. Emphasizes the features、work theory and earthing of the isolated barrier, which is used in intrinsic safety explosion-proof industry process control system .

Abstract: The synergetic effects of the substitution of Ti and Si for Fe on the crystallographic structure and magnetic properties of Nd₂Fe_17-x-yTi_xSi_y compounds have been comprehensively investigated by means of x-ray diffraction, neutron diffraction and magnetic measurements. Rietveld refinements of the diffraction data indicate that all the samples crystallize in the rhombohedral Th₂Zn₁₇-type structure. For a given Ti content, the a-axis and the unit cell volume V of Nd₂Fe_17-x-yTi_xSi_y decrease linearly with increasing silicon content, while the c-axis behaves complicatedly dependent on different Ti content. The site occupancies of Ti and Si in the crystallographic sites significantly change compared to what is observed in the corresponding singly substituted compounds. The T_C of doubly substituted Nd₂Fe_16.5-yTi_0.8Si_y and Nd₂Fe_16.5-yTi_0.5Si_y is higher than that of singly substituted Nd₂Fe_16-ySi_y for a lower Si content while the converse behavior is observed for a higher Si content. For a given Ti content, the T_C of Nd₂Fe_17-x-yTi_xSi_y compounds increases with increasing Si content and the M_s first increases and then decreases. The M_s of Nd₂Fe_17-x-yTi_xSi_y decreases with the increase of Ti content.

Abstract: A novel posture alignment system based on 3-DOF locators is presented to meet the finishing need of big part such as wing after assembly. The system includes three locators for posture alignment and auxiliary clamping devices for auxiliary clamping. The structure and basic principle of device and the posture alignment principle are introduced in details. The application show the system could meet the posture alignment and finishing need of big part such as wing and provide a reference for aircraft assembly and fabrication.

Abstract: Using the finite element software “ANSYS” to establish the three-dimensional coupled model in magnetic field and temperature field during the process of transverse flux induction heating of ring-shaped heater and Square-shaped sheet steel, this paper studies the distribution laws of the magnetic and temperature fields in the induction heating process. Through studies, the calculations show: 1) The distribution of the magnetic fields and eddy cavities in the sheet workpiece is in the shape of ring; has close ties with the shapes of the coils; 2) The intensities of the coils’ magnetic field and eddy cavities reach the strongest in the projection of sheet metal, and the temperature in the projection part also rises the fastest. For the purpose of verification, the induction heating experimental plat is established to measure the changes of temperatures of numerous points in the plat and to compare the changes with the calculations. Via the comparison between the simulation results and the experimental measurements, the results of numerical simulation are confirmed reliable, and can be used as the theory and the experimental basis for the design of the induction heating system.

Abstract: 3D printing technology is one additive manufacturing technology which involves mechanical, electronics, optics, materials and other disciplines. The domestic and foreign research status are introduced. The applications in the mechanical aspect are especially analyzed. The problems in the applications and the prospect are discussed at last.

Abstract: This paper presents a new strategy of analysis and compensation of non-linear error. Non-linear error is an important source of machining error in multi-axis numerical controlled machining and it is unavoidable. In view of tool positions optimization in five-axis CNC machining of complex surface, this paper presents a strategy for non-linear error compensation in five-axis machining: Firstly, non-linear error caused by the change of tool axis vector is analyzed and the non-linear error model is established, in order to get the maximum non-linear error of interpolation segment; Then, the tool position that meets the machining accuracy is obtained; Finally, Simulation and analysis of the model show that the proposed method is effective and greatly improves the geometric accuracy.

Abstract: In the mechanical products, there are always some poor stiffness and high precision thin-walled workpieces which will produce deformation in the machining process easily, so it is difficult to control the machining accuracy and to meet the requirement of higher machining accuracy. Based the finite element numerical simulation key technology, this paper analyzes the machining deformation, including geometric model simplification, mode selection, dynamic loading, a 3D simulation model of thin plate features establishment. Through the finite element numerical simulation analysis of the thin plate, we analyze the influence on processing deformation from different processing parameters and different constraints.