Advanced Materials Research Vols. 472-475

Abstract: This paper is focused on the mechanics and deformation performance of mine stope after excavation. The deformation performance is described by the settlement of stope roof, and the mechanics performance is described by the plastic zone of rock mass surrounding stope. The numerical calculation software FLAC3D is used to simulate the deformation and failure situation of the rock mass surrounding complicated large underground stope. In the calculation, the excavation procedure for the stope is simulated. The mechanical method has been adopted to establish the analysis on the stope stability, the results are in accordance with the actual situations, and can help to more accurately predict location of failure. The conclusion can give some guidance for the real practice.

Abstract: The CNC programs which are automatically generated by software for cutting paths become more complicated while parts are complicated and precise, so it is difficult to assure CNC programs accurate. Discharge electrodes to fabricate models of DVD boxes are machined as case study in this paper, the CNC programs are verified accurately by simulation of VERICUT software.

Abstract: Numerical simulation of the secondary cooling is applied to the design of continuous casting. The mathematical model for solidification process of the strand under air-mist was established and calculated with the finite element model. The model is used to calculate the feasible operating range of the continuous casting machines. The dynamic secondary cooling system has been analyzed with consideration of the thermo mechanical principles and numerical model. The adequacy of the model has been confirmed with experimental results.

Abstract: Phenyl isocyanate is used to react with 1,3-butanediol at different temperatures. Dimethylformamide is used as solvent. In-situ FT-IR is used to monitor the reaction to work out rate constant, Arrhenius equation and Eyring equation. The urethane reaction has been found to be a second order reaction, and the rate constant seems different between initial stage and final stage. The activation energy (Ea), activation enthalpy (ΔH) and activation entropy (ΔS) for the urethane reaction of primary hydroxyl group are calculated out, which are 90.9 kJ•mol^-1, 88.2 kJ•mol^-1 and 20.2 J•mol^-1•k^-1, respectively. They are very useful to reveal the reaction mechanism.

Abstract: The work environment and the feature of the subframe have been discussed though the fatigue test on the subframe of original design. Fatigue simulation environment of the original subframe was established and analyzed under assistance of optimization software. After comparative analysis with test environment, the construction of the fatigue simulation environment model was considered more reasonable. Meanwhile, fatigue simulation analysis, under the original simulation model, was conducted on the subframe of new materials. After a comparative analysis with general steel subframe, it was concluded that fatigue life of new subframe was greatly improved while the lightweight.

Abstract: The influence of the apparent viscosity and pouring temperatures of the semi-solid aluminum alloy on filling and solidification process of the housing cap bearing under the condition of die casting was analyzed using numerical simulation method. The results of simulation show that the mold filling velocity of the semi-solid aluminum alloy decreases markedly with increase of the apparent viscosity. The influence of the pouring temperatures of the semi-solid aluminum alloy on the mold filling velocity is consistent with that of the traditional die casting. The solidification temperatures at the same position of the casting increase with increase of the apparent viscosity of the semi-solid aluminum alloy. There is no casting defect in the casting after complete solidification.

Abstract: In order to solve the problem that how to evaluate the complex system support concept, an evaluation method based on Radial Basis Function (RBF) neural network model was presented. Through researching the support system overall design characteristics and elements of support, on this basis, evaluation parameters of support concept were abstracted. Support concept evaluation model based on RBF was established and a mature and stable RBF neural network was trained to calculate the comprehensive evaluation value for support concept. Finally, the further demonstration and verification of the method are given through specific case application and compared with the result for evaluation results of data envelopment analysis (DEA) model.

Abstract: In order to improve the riding and handling of the vehicle，the full-vehicle dynamical model of a certain vehicle is established by means of the software Adams/Car．The design of multi-objective optimization was used for Suspension system parameters on the base of the dynamical model．The optimized results show that riding of the vehicle is retained and dynamic load of wheel is improved obviously．It can be concluded that the optimization method is feasible for the optimization design of suspension system parameters．the investigation also supply the basis of theory for design considering the matching of the suspension system parameters.

Abstract: Polyurethane-modified epoxy resin was prepared with Polyurethane prepolymer(PUP). The effects of the PUP content and epoxy resin type on mechanical and thermal properties of materials were discussed. The results indicate that the tensile strength and impact strength of the material increase to maximum successively, and then decrease with the increasing addition of PUP. When the mass fraction of PUP was 15%, the tensile strength and the impact strength of materials were all the best. There were significant differences in mechanical and thermal properties of material for different epoxy, and the best results were cured epoxy TDE-85.

Abstract: This paper deals with the study of power consumption in the discharging process of polymer particulate solids in a vane plasticization extruder. The structure and operating principle of the innovational vane extruder are completely different with conventional screw extruders. The process of conveying materials in vane extruder is based on volume transportation. Solids conveying zone is the first section of polymer processing in extruder. Large amounts of energy are consumed in the zone. The solids conveying process is composed of feeding, compacting and discharging process in the vane extruder. The discharging process is very unique and worthy of further study because of the particularity of the vane extruder. A mathematical model has been developed to analyze the power consumption in the process. The model shows the structural parameters have significant influence on the power consumption. In addition, the model is verified by experimental results.