Key Engineering Materials Vol. 620

Abstract: The influencing factors of technical parameters on blanking fracture surface quality are quite few and complicated, including clearance, speed, die roughness and punch radius. And determination of these influencing factors and optimization of the process parameters combination are vital to the blanking with stability and duration. The determination of these parameters depending on experience of designer in production leads to a longer development period and higher cost in testing modes. In the current study, a kind of prediction method for fracture surface quality was put forward by using nonlinear mapping properties and learning capacity of the support vector machine theory in which nonlinear input can be mapped into higher dimensional space by selecting kernel function RBF, and compromise parameter with C=0, and expectation error of ε=0. 1. The final production model was obtained by practice with orthogonal experiment of four factors times three levels. Experimental verification was conducted by selecting a number of test data. Results have shown that the predicted values were in good agreement with those from tests.

Abstract: As a new kind of cutting and grinding tool, diamond-bead wire has gained multi-patterns and many applications. It is commonly comprised of six elements pertaining to corresponding roles for the capacity of the wire: wire rope, diamond bead, clip, spacer, joint, spring or plastic/rubber. For further systematic understanding of diamond-bead wires, researching and developing new bead wires,and making full use of bead wires, it is desperately needed to properly classify diamond-bead wires available and those that may exist in theory. The current study collected and analyzed systematically a hundred of patterns of diamond-bead wires from the diamond-bead wire manufacturers throughout the globe went insight into the essential elements of the wire, including the overall layout, shape characteristics, technological processes, cutting and grinding object, and studied in classification for the spectrum characteristics. And the structural feature covers skeleton package, spacing washer, and special structure; manufacturing process contains bead manufacturing methods and the wire producing processes; and sawing object includes the soft stone, hard stone, and other substances. A trial spectrum has been drawn on the POS classification. All the subjects were discussed and presented in two parts, and here is the first part for classification with processes and objects.

Abstract: Three forms of model parabolic bulldozing plate were designed and manufactured. Their macroscopic soil-engaging surface directrixes consist of parabolic curve and the cutting angle were 50°, 55°and 60°respectively. The working resistance was measured by a homemade indoor soil bin. The parabolic moldboard model with a cutting angle of 55° has the least working resistance. On this basis, the parametric equations of three kinds of macroscopic soil-engaging surface of parabolic type moldboard were established. The intrinsic geometrical quantities of the macroscopic soil-engaging surfaces, including the first base quantity (E, F, & G) and the second base quantity (L, M, & N), were calculated. Compared with the working resistance test results of the three moldboard models, it is found that there is a specific range of E value in first base quantities and L value in second base quantities which can make the soil-engaging surface to obtain lower resistance. This research provides a reference for the resistance-reducing and energy-saving design of macroscopic soil-engaging surface of moldboard.

Abstract: Composite (multiple) bead wire is an important machine for stone-sheet production with efficiency, but it takes up space, with big energy consumption, uneven thickness, and noise. The current study aims at optimal designing a bead saw with energy-, material-saving, and being light in weight under the constraint of the strength, stiffness and stability for the frame. A 140 rope saw, as a prototype and one of the applications, discussion of two main frames were done with the layouts consisting of the driving wheel, guide wheel, and the supporting wheels from a variety of structural Patterns. By comparison between the triangular and rectangular layouts, a conclusion was drawn that under the condition of all other things being equal, rectangular layout is more reasonable; each wire is supposed to be adjusted for the uniformity of tension of the whole wires. The objective function was taken as the sum of the mass expression of each component of the frame with a series of punishing factors. The hollow structure of double columns with guide grooves and special beams were got, achieving design goals.

Abstract: In this paper, turn the medium of magneto rheological liquid into continuation, and using of the critical Reynolds number determine method of liquid move state and compound with non-Newton fluid, get the conclusion of finished machine abrasive magnetic liquid fluid as laminar fluid, for having no mathematics’ model practical or be fit with the experiment, especially the distribution of shear and velocity stress, In this paper, using of the critical Reynolds number to determine the liquid state of magnetic fluid state, and in determined the fluid state, using non-Newton fluid dynamics and tensor analysis theory and also compound with the double dynamic viscosity model, analysis the abrasive magnetic fluid quality of kinematics shear stress, according to the quality, contracture the dynamic model of abrasive magnetic liquid finished machine, during the interfere, using the double viscosity fluid model, we may get the conclusion, liquid magnetic abrasive, when the shear stress more or less the bend stress, and mark with plasticity viscosity η_p0 , η_pγ which round the work piece center, the velocity distribution as laminar, and also, analysis the flow field mathematics’ model by the finite element, and also going on the numerical simulate for the magnetic fluid velocity field of finished machine.

Abstract: According to the main problems of nonlinear driving control and driving force calibration of pure electric vehicle, based on the research of permanent magnet synchronous motor control method, on the vehicle's driving force calibration techniques were studied, from the high efficiency and energy saving analysis of necessary driving force calibration, designed a new driving force calibration method, and drew the control curve of the accelerator pedal opening and the speed and the motor torque relationship between the three, and finally to pure electric self-developed to test platform for automotive related experiments. The experimental results show that, in the vehicle driving process, the driving force calibration technique compared with the previous calibration has better performance, while no obvious change of acceleration performance, the current value of the initial acceleration phase have been greatly decreased, could make the vehicle run more energy efficient, extended battery life and vehicle driving mileage.

Abstract: The rail wagon coupler is casting part. Some of foreign products’ error dispersion is significantly greater than domestics’. What influence generated by the results acting on the actual use of performance is still not clear. To this end, this article studied the influence generated by the angle of surface S tangent of coupler-knuckle on coupling connection contour and starting bearing line (referred to as surface S angle) to traction reliability, coupling feasibility and acting force in tangent line, systematically. And authors explored the value ranges of surface S angle in order to ensure the operation performance of coupler-knuckle. Firstly, find the major factors which are associated to surface S angle by studying the movement mechanism of coupling and traction. For example, the maximum level angle of coupler-knuckles, the ability for vehicle to pass the curves, etc. And then, get analytical expression of coupler surface S angle and related factors by means of theoretical derivation. After that, obtain value ranges of surface S angle. Finally, carry on experiments with multi-body dynamics simulation software RecurDyn. On the one hand, eliminate unreasonable value ranges obtained by theoretical derive, on the other hand, analyze the changing rule of the acting force on coupler-knuckle contour. The results prove that, when coupler surface S angle is , the traction performance of coupler is relatively stable, the coupling performance is relatively reliable, the contact force on coupler-knuckle contour is smaller. The conclusion is consistent with surface S angle parameter required by the standard system of Association of American Railroads. The research results above provided the theoretical basis for improving coupler’s manufacturability.

Abstract: E-ACE (acrylic elastomer) is a kind of material so far in electro-active polymer (EAP) in the most excellent performance. Based on the analysis of the basic principle of the E-ACE power generation, the feasibility is studied on E-ACE power generation principle to achieve energy recovery and damping. Design a model damping device of vehicle for energy recovery based on E-ACE. Through analysis, when the system vibrates near the resonance frequency, deformation of spring is greater, E-ACE materials to move up and down reach the larger amplitude, and the more energy it produces. To analysis the system about harmonic response by ANSYS software, get the relationship between spring stiffness K, damping coefficient C and external incentive, then analysis the resonance frequency of the system. The simulation results verify the feasibility of the design scheme. Results show that E-ACE has excellent performance in the automobile vibration energy recovery and vibration. E-ACE will have broad application prospects.

Abstract: In this paper, a theoretical mechanical model for the brake shoe is set up according to the foundation brake unit of railway freight cars, and it indicates that the friction moment is the origin resulting in brake shoe eccentric wear. On this basis, the pressure distribution formula on the brake shoe is derived when the train brakes in forward and backward direction respectively. The analysis results show that if the wheel and the brake shoe are concentric, the ratio of the revolving-in end pressure to the revolving-out end pressure in wheel forward revolving is larger than that in wheel backward revolving. It is consistent with the phenomena that upper eccentric wear often appears on the brake shoe in practice. Further research reveals that the degree of the eccentric wear is determined by the braking force action style, which is the theoretical basis for the design revision. In addition, the RecurDyn Multi-body Dynamics software is used to build the rigid-flexible coupling dynamics model for the foundation brake unit. The simulation experiment verified the analysis result. The research outcome provides the theoretical basis and technical support for further design improvement of the foundation brake unit in railway freight cars.

Abstract: In order to solve the automatic localization problem of the surface or curve detection, this paper presents a method for obtaining a global optimal solution, the method uses particle swarm algorithm to solve the position and orientation. To solve the problem of premature convergence and slow convergence in particle swarm algorithm, a chaotic mapping logistic model is presented to improve the performance of particle swarm algorithm and the shrinking chaotic mutation operator is applied into the method to increase the diversity and ergodicity of particle populations. In this paper, the objective matrix is separately described by quaternion and Euler angles, and the accuracy and convergence of the algorithm are analyzed taken into account these matrices. Simulation results demonstrate that two mentioned expressions can comply with the requirements of adaptive localization, and while Euler angles as optimization variables, chaotic particle swarm optimization have higher accuracy results. Finally, compared to Hong-Tan algorithms, the method is effective and reliable.