Advanced Materials Research Vol. 510

Abstract: A finite element model is designed to obtain the mechanical parameters about cushioning property of multilayer regular triangular honeycombs under the in-plane crushing loadings with high impact velocities. A simplified energy absorption model is put forward to evaluate the energy absorption performance, which shows that the optimal energy absorption per unit volume is related to dynamic plateau stress and dynamic densification strain. Both depend on the configuration parameters of representative cell and impact velocity. From the physical analysis and discussion of the numerical results, the empirical formulas of dynamic densification strain and dynamic plateau stress are suggested in terms of configuration parameters and impact velocity. Based on these empirical formulas, a feasible cushioning optimization algorithm is put forward and presented.

Abstract: The hot compressive deformation behavior of the superalloy was investigated at the temperature range from 1050 to 1140 and strain rate range from 0.01 to 10s^-1 on Gleeble-1500 thermal simulator. Utilizing hyperbolic sine function and introducing the strain with 4th order polynomial fitting, the constitutive equations of flow stress of spray-forming FGH95 superalloy at high temperature were established. The results show that during the hot compression deformation of the superalloy, the characteristics of dynamic softening were observed, and flow stresses decrease with increasing temperature and decreasing strain rate. The flow stress of the superalloy predicted by the proposed models with 4th order polynomial fit agree with the experimental value well, and the average relative error is 3.64%.

Abstract: The finite element models of bladed disks with different lashing wire locations were established. The natural characteristics and mode shapes of bladed disks with different lashing wire locations were compared, and the effect of lashing wire location on the natural characteristics and mode localization of bladed disks were analyzed. These results show that different lashing wire locations could carry different natural frequencies to bladed disk, and there must be one lashing wire location with the highest frequencies. Lashing wire location has a significant influence on the mode localization of the mistuned bladed disks, and the mode localization of the bladed disks is less sensitive to mistuning when the lashing wire is in the middle of blades.

Abstract: This paper presents the structure design, the working principle and the relevant calculation of the mechanical clamping claw of the land rigs automatic arranging drill pipe system. Applying the Generative Structural Analysis module of the CATIA, we can get the Von Mises stress image to show the stress distribution. The finite element analysis provides a simple effective method for the design of the structure of the mechanical clamping claw. Through this device the drill pipe can be transferred automatically and circularly from the rat hole to the pipe racking system and from pipe racking system to the mouth of the well.

Abstract: Automatic" and "less people" in fully mechanized working face is the target of China's coal industry development, and the key to achieve this goal is the automation of coal mining. According to the previous technology of memory cutting cannot adapt to the complicated geological condition in China, this paper proposed the technology of shearer self-adaptive memory cutting based on fuzzy control theory, the shearer positioning system and fuzzy control system of self-adaptive cutting. These systems can get the message of shearer's position and attitude at any point, trace the memorial cutting path automatically, judge whether the shearer cuts rocks based on fuzzy control theory and find the optimal scheme when it works. The authors make the experiments of path tracing in laboratory and the experiment of shelf-adaptive adjust in Xi'an Coal Mining Machinery. All the experimental results show that this technology not only can realize the shearer memory cutting, but also can discriminate the abnormal state of shearer cutting rocks, then adjust the drawing speed and drum height automatically.

Abstract: A simple method for fabricating silver circuit patterns on polyimide (PI) substrate was developed. Firstly, partially potassium hydroxide (KOH) modified pattern was produced on the surface of PI film via a screen printing process. Then the silver ions were doped into the interior of the PI substrate through an ion-exchange reaction. Finally, the silver circuit patterns with the lines of 200 µm width were formed on the PI substrate surface due to the reduction reaction of dimethylamine borane (DMAB). Scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, infrared spectra (FT-IR) and contact angles analyses were conducted to study the morphology, composition and structure of the obtained silver patterns on the PI substrate. This approach is simple and versatile, and need not the expensive apparatus, which is a promising candidate for a broad range of application in high-density circuitry electronic industry.

Abstract: In order to study the problem of stability-losing load of the super-big crane jib with the inverted-V shape, this paper completed theoretical analysis, simulation and verification. Based on the stability-losing load formula considering shearing-force influence of compressed solid column, the limit load formula of the inverted-V combinatorial jib was obtained. Then, the method of force was applied to getting the shear angle formula of the inverted-V combinatorial jib under unit shear load. After using the proved formulas and software SAP2000 in linear buckling analysis of 28 combinatorial jibs consisting of two kinds of typical-section rods, the results demonstrated that: As for combinatorial structure consisting of cross-shaped web members, the error between results of the proved limit load formula and finite element calculation was within-5% when the aspect ratio of the inverted-V combinatorial jib was above 3.

Abstract: Remanufacturing is a new manufacturing mode in modern manufacturing environment. This paper had a survey on the uncertain problems in project-based remanufacturing system based on the analysis of the conception of project-based remanufacturing. On the basis, the uncertain problems in project-based remanufacturing systems, which including the uncertain factors, the description approaches for uncertain factors and the strategies to reduce the uncertain influence factors, was studied in detail based on the characteristic of project-based remanufacturing systems.

Abstract: Aimed at the shrinkage and deformation of U-shape part in cooling process after hot forming, the RBF model is established to predict the deformation and direct the die modification. The main factors influencing deformation were set as the design variables and the sample data were obtained using Latin Hypercube Sampling. From the FEM simulation results based on these samples, the deformation was taken as the response.The forecasting value of RBF model is compared with that of FEM. The error is smaller than 1.78% and the RBF predicting model has enough precision. At last, the compensation of deformation on the die-face was made based on the displacement vector of node during the cooling process and the forecasting deformation by using RBF model. The results show that the dimension error of the U-shape part produced by the modified die is lower than 0.3% and the accuracy can meet the production requirement.

Abstract: Tilting torque of the converter is one of the fundamental and most important parameter. Many factors affect the calculation of converter tilting torque, especially furnace structure. By applying the 3D-CAD to calculate the converter tilting torque, we make a dynamic analysis and get the tilting torque, which provides theoretical basis for its improvement.