Applied Mechanics and Materials Vol. 722

Abstract: Using titanium trichloride (TiCl3) as the precursor, sodium chloride (NaCl) as the mineralizer, cetyltrimethyl ammonium bromide (CTAB) as surfactant, titanium oxides (TiO2) nanomicrospheres were synthesized by hydrothermal method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were employed to characterize the crystal structure and morphology of the microspheres. The results indicate that the spheres were rutile with diameters of about 1μm ~5μm. The spheres were composed of radially aligned nanorods with diameters of about 40nm and lengths of 500nm. The influences of the concentration of surfactant and the concentration of mineralizer were also researched. The microsphere diameter and grain size both reduce with the increase of the concentration of CTAB. The microspheres get larger and more complete with the higher mineralizer concentration.

Abstract: Cationic polyacrylamide is a derivative of polyacrylamide, a cationic polymer flocculant which has an excellent effect on sewage treatment. Our existing cationic polyacrylamide are mostly prepared by the Mannich reaction ,which has the shortcomings of more unreacted material, low cationic degree, poor stability, short validity, etc. Therefore, a cationic polyacrylamide has been prepared by aqueous solution.P(DAC-AM) was synthesized by aqueous copolymerization of acrylamide (AM) and DAC using complex initiated system consisted of (NH₄)₂S₂O₈,NaHSO₃ and V-50. Mass percent of monomer, amount of initiator, content of cation monomer, pH, reaction time et al on the effect of intrinsic viscosity of polymer were discussed. The suitable conditions of synthesis were concluded. Mass concentration of monomers:35%, initiator amount 0.06 %,V-50 amount 0.005%,pH:5.5~6.5,urea concentration 0.1%,EDTA 0.02%,β-dimethylaminopropionitrile concentration 0.03%,reaction time 5~6h,the intrinsic viscosity of product is 13.95dL·g-1.

Abstract: Based on Backofen constitutive equation of 5A06 aluminum alloy at high temperature tensile test, get 5A06 aluminum alloy best superplastic constitutive equation parameters: when T= 400°C,m=0.39, K=270.34.5A06-O aluminum alloy cup gas bulging forming process is simulated with using the method of MARC finite element analysis .By designing a variety of shapes of bilge preform die, to align the bulging parts first post mode when carries on the different effects of the thinning deformation, and analyzes its influence on cup final thickness distribution of the rule.The superplastic test and positive and negative bulging simulation study results of 5A06-O aluminium alloy plate for commercial supply condition (the original thickness of 2 mm) show that the optimized blow the thinning deformation is greatly improve the cylindrical pieces of the final wall thickness distribution, the most in thin wall thickness from the simple was blowing bulging of increased by 0.94 mm, 0.65 mm Wall thickness distribution index is 0.079.

Abstract: This paper analyzes the micro-mechanism of interaction between femtosecond laser and one dimension material. It gets the figure of temperature change with time by calculating the Two Temperature Equation(TTE) in the process of the laser ablation. And it presents the surface characters of metal material. Additionally, the plasma is generated when the temperature of ion subsystem is far higher than the melting point of copper metal. The paper can give the laser ablation threshold by the numerical calculation. It will help the researchers ensuring the laser fluence for preparing the copper film better.

Abstract: Orthogonal experiments of ultrasonic deep rolling with Longitudinal-torsional vibration (UDR-LTV) and conventional deep rolling (CDR) 6061-T6 aluminum alloy were carried out. The experimental results were analyzed by orthogonal-response surface methodology to study the effects of processing parameters on surface roughness. The results show that the values of surface roughness obtained by UDR-LTV are smaller than that of CDR with the same processing parameters. Meanwhile, feed-rate has a marked effect on surface roughness, and static pressure has a little effect on surface roughness. The quadratic regression method is used to construct the mathematic model of surface roughness based on the experimental results. The interactions between the processing parameters are analyzed using response surface method. The optimal parameters for the lowest surface roughness are given, which provide technical support for proper parameters in practical processing.

Abstract: The numerical simulation of the cross-rolling stainless steel/carbon steel double metal composite seamless steel tube process was conducted through the finite element analysis of the three-dimensional thermo-mechanical coupled elastic-plastic by applying the MSC.MARC software. Based on the numerical simulation, The character of stress, strain and temperature distribution parameters during the two roll cross-rolling were obtained by the finite element analysis, and acquired the section pass deformation figure. The distribution of the axial stress, circle stress and radial stress were drawn in the cross-rolling roll gap profile along the circle. The mechanism of tube cross-rolling process was explained according to the stress distribution. The results of the research can be applied to the design of the cross-rolling forming process.

Abstract: The dynamic load strength test of automotive BIW is an important parameter for vehicle passive safety, but different test standards, different test requirements, which caused much trouble to the test authority. To solve the shortcomings of the traditional machines, such as low automation, poor universality and weak ability of data processing, this paper designs a new test machine for the dynamic load strength trials of automotive BIW on the basis of three typical standards. The test results indicated that this test machine embodies the characteristic of easy operation, stable function, and wide suitability, which improves the measurement accuracy and efficiency, at the same time, solves the problem of the database construction.

Abstract: Jets obtained from shaped charge at different cone angle are simulated using Euler solver in Autodyn-2D Hydrocode against a 56mm-diameter of the charge. An OFHC copper liner of thickness 0.8mm and 54 mm-diameters is used for jet formation analysis. Point detonation method is used for Charge ignition. The simulation results are presented at 30 micro-second after initiation. Energy behavior is predicted at different obliquities. Numerical simulations are compared with the existing experimental results for liner angle 60. The depth of penetration and volume of the crater produced is measured. It is observed that simulation results are in good agreement with the experimental results. Flash X-ray Radiography was used for image capturing. It is observed that kinetic energy of the jet decreases as angle increases, also total energy of the explosive increases and hence the Ratio of the K.E of the jet to the total energy of the explosive decreases as the angle increases. The volume of the crater produced in steel at 65° has the highest value among the jets considered, so it can be used in oil well perforation also.

Abstract: Transmission system is an important part of combine harvester, and is the main indicator to measure the level of technology. This paper presents the design of a composite hydraulic mechanical transmission system for combine harvester. The system consists of engine, variable pump, quantitative hydraulic motor, planetary reducer, driving wheel, crawler etc. Author analyzes the continuous variable speed regulation characteristics of transmission; determines selection method of hydraulic components and mechanical parameters. Composite transmission system can make the engine is close to full load operation, improve combine harvester productivity and fuel economy. By optimizing the transmission system, combine harvester can reduce speed, increases the torque, realizes continuous variable speed. Practice has proved: this dynamic composite transmission system with fast response, high efficiency, and reliable, low failure rate. At the same time, combine harvester has the advantages of simple operation, forward, backward or turning without shifting, greatly reduce the labor intensity of the operator.

Abstract: Multi-objective optimization technology and Fuzzy theory were applied to design truck differential based on consideration on its force condition. The mathematical model for the multi-objective optimization design was set up under the objective of the minimum volume of the differential, maximal strength of planet gear, with the design variable of planet gear teeth number Z1, axle shaft gear teeth number Z2, section modulus ms and working width b. Then, the fuzzy solution of multi-objective optimization were use to solve the model. Practical example of calculation shows that, the fuzzy optimization result is superior to that of regular optimization and traditional design, differential volume deceased by 32.73% and 1.92% respectively. Comparing with nominal design, the load of planet gear increases 17%, but is far below its permissible value, and also reduced by 9.04% than that of regular optimization.