Advanced Materials Research Vols. 785-786

Abstract: The expressions of voltage, stress and amount of charge of monocrystal piezoelectric generator under concentrated exterior pressure was derived in order to proving the precision and validity of numerical method applied to piezoelectric materials' distribution sensing and the study of operation mechanism ignore the influence of adhesive layer. An analytical model of the monocrystal piezoelectric generator was established by using the mechanical vibration theory. And the effects of the structural and material parameters on the output energy are analyzed.

Abstract: Dynamic contact model of rough surfaces can provide the theoretical basis for analyzing the microscopic damage of surfaces in wear process and constructing the analytical wear model to predict wear. A dynamic contact model of sliding rough surfaces is innovatively constructed based on the characterization of the contact asperities on rough surfaces in this paper. Firstly, an asperity model of rough surface is set up according to the surface topography parameters and the static contact parameters is evaluated in the light of statistics contact theory; Then the contact characteristic of surface topography in sliding is analyzed and a series of equivalent contact models are proposed; Finally, the dynamic contact model of rough surfaces is established and from which the dynamic contact parameter of rough surfaces is formulated. The dynamic contact model can be further improved to analyze the friction fatigue wear of sliding pairs and provide reference for tribology design of mechanical surfaces.

Abstract: The rump pan is the body and the load-carry device of Scraper conveyer. the material is ZG30MnSi. In order to improve the life of the casting.this paper simulated filling and solidification process of rump pan by Procast software,and predicted the position of shrinkage cavity and shrinkage porosity in castings.Then through improving gating system and add reasonable risers, optimal process parameters scheme is got.

Abstract: Gear transmission with a small number of teeth is widely used as a key component of mopeds, motorcycles, electric bicycles and so on. A parameter design of cylinder gear pairs with small number of teeth was put forward, which was carried out by establishing a optimization model and selecting the preliminary parameters of gear pairs, and then adjusting the parameters according to the meshing interference conditions and the strength theory. The parameters of the compact gear pairs, which meet transmission quality requirements and strength condition tested by finite-element analysis, can be obtained ultimately. The feasibility and rationality of this method are verified by case.

Abstract: It explored how to create visual motion feeling with an aesthetic viewpoint Dynamic in Statics from the basic function and structure of packaging container molding. In this paper, it analyze the following as the barycenter and momentum of container molding, the dynamic feeling off horizontal and vertical, the dynamic feeling and the change of body structure, the dynamic modeling of ornament shape. And then it also discuss the following as the independence and relevance of local and whole shape of container structure, the coordination of molding form and perception, which present study and design points for Dynamic in Statics of packaging container molding, and also put forward a art form and some state requirements on Dynamic in Statics for shape design.

Abstract: In order to research and design the vortex rings umbrella, finite element analytical approach is integrated to design the complicated vortex rings umbrella. Three-dimensional geometrical model of vortex rings umbrella is constructed from the feature of non-linear ductile deformation, and it establish kinetic model of particle node at the stage of steady state rotary motion, finally build simulation model. The calculation shows that motion variation laws of its result and experiment result are basically same, the model is deemed effective and correct. This research can help rapid realization of engineering design of vortex rings umbrella and provide a new thought for the research of motion performance of vortex rings umbrella.

Abstract: This paper takes the Q345 steel as an example, adopting finite element simulative analysis to study the influence of solid-state transformation on welding residual stress. By setting the value of the thermal strain in different temperature, the change in volume caused by the phase changes is equivalent to the thermal strain. Simulation includes two cases which are consideration of phase transformations and not consideration. The results showed that the distribution trend of the longitudinal stress of the weld zone is substantially the same in the two simulations. In the case of not consider the simulation of phase change, there is a lot of stress in the weld zone and the heat affected zone and the maximum value could be 427 MPa. In regard to transverse stress, phase change not only affects the value of the stress, but also changes the direction of the stress of the weld middle portion. Welding residual stress is also measured by X-ray. Phase change simulation and experimental results are in good agreement, it can be concluded that phase change in the welding process will result in a significant impact on the distribution of the residual stress, which could not be ignored in the finite element simulation of welding process.

Abstract: The adhesive-bond of paster single lap joints was put forward firstly. The strength of 5052Al-Al adhesive-bond of single lap joints (SLJ) and 5052Al-Al paster adhesive-bond of SLJ were investigated using finite element method (FEM). Results from the simulation showed that the paster adhesive-bond of SLJ was stronger than the adhesive-bond of SJL. So it can use the paster adhesive joints to improve the strength of adhesive joints.

Abstract: An improved dynamic constitutive model is presented, aiming to describe the key mechanical properties and predict the bearing strength of concrete structure under static and dynamic load. This model is based on the concept of equivalent uniaxial strains and strain rate. In this paper, an equivalent uniaxial stressstrain curves are obtained by the WillamWarnke curve and take the same form as in Saenz models. Then, the bending strength of a concrete beam under different static and dynamic load was discussed.

Abstract: With the development of the car industry, the pace of the urban construction is accelerating as well. Cars have gradually entered the ordinary family. As the car noise has a big effect on the health of the passengers, as well as on the surroundings, one of the car industry key duties is the car noise reduction. By researching the materials applied to car, this article describe that PU material could reduce the impact of the engine noise on the cab efficiently; Polypropylene needle-spun felt could reduce the noise passed by chassis; PET material's sound absorption is poor in mid bass, however in high frequency it's sound absorption is good; sound absorbing sponge can reduce the low and high frequency noise; The combine sponge can reduce the noise from the tire and transmission system ; Cotton material could absorb the high frequency noise.