Advanced Materials Research Vols. 393-395

Abstract: The microstructure and mechanical properties of 15Cr super martensitic stainless steel after different heat treatments were studied. The results show that the structures of the steel after quenching are lath martensite. With the raising of the quenching temperature, the original austenite grain size increases and the martensite platelet gradually coarsens. The microstructures of the tempered steel are tempered martensite and reversed austenite dispersed in the martensitic matrix.

Abstract: This template explains and demonstrates how to prepare your camera-ready paper for Trans Tech Publications. The best is to read these instructions and follow the outline of this text. FePt nanoparticles with spherical shapes were prepared by reduction of Fe(acac)3 (acac = acetylacetonate) and H2PtCl6•6H2O in the presence of surfactant poly(N-vinyl-2-pyrrolidone) (PVP). XRD, TEM and VSM results confirm that the PVP contents affect rarely the morphology and crystal structure of FePt nanoparticles, while result in a big change of their magnetic properties. The highest coercivity up to 5.2 kOe was obtained at PVP / FePt molar ratio of 7.0.

Abstract: Pure 304L powder is used to mix with an additive to prepare a powder mixed paste. 304L honeycombs are fabricated by extruding the powder mixed paste, then dried and sintered. When sintering at 1150°C, 30minite, powder particles bind together and become grains. The structure parameters of and properties of sintered honeycombs were obtained by measuring and calculating. Results show that wall thickness 0.15~0.20mm, cell number (1/in2) 330~365, clear cross section (%) 73~79, specific surface Sv(sq m/cu dm）2.52~2.68; specific heat capacity Cp(J/g.K) 0.6~0.7, heat conductivity κ(W/m.K) 10~12; transverse compression strength 40~50 Mpa, longitudinal compression strength 140~150 Mpa. SEM/EDS analysis shows that the surface of sintered honeycombs is really rough, the structure of sintered honeycombs consists of matrix phase α-Fe(Cr,Ni) , complex compounds of silicon, iron and inclusion elements distributed in matrix . There is oxide film forming on surface of sintered honeycombs.

Abstract: In the process of preparing superfine wood-flour with physical method, when the size of wood-flour particle reaches to the corresponding level, a single wood cell will be destroyed. In the process of analyzing micro-nano wood-flour’s cutting power, the process of cell disruption of the wood cell needs to be computed. Based on the relevant theory of finite element and structural mechanics, this article builds a structure mode of 12 lever hexagon truss model to simulate the cellular structure. There are 6 levers outside to simulate the cell and 6 levers inside to simulate the internal pressure. This establishes a single cell stress model to analyze its stress. It can be obtained that when the size of the force acting on the node reaches the unit force, the minimum tensile stress of the bar element is bigger than the macroscopic tensile strength of the wood. According to the structural characteristics of the cell wall, this paper compares the tensile stress along the grain of the bar element with the tradition cutting stress. Using tensile strength as the criteria to test the rupture failure of Cryptomeria fortunei cell, the wood cell’s disruption force can be concluded. When preparing superfine wood-flour with Cryptomeria fortunei as experimental raw materials, the calculated results of applying the traditional cutting theory to calculate the cutting force has proved the analysis structure of Cryptomeria cell micromechanics with the method of finite element and structural mechanics, so that it can be concluded that certain cutting force can make Cryptomeria fortunei cells disruption.

Abstract: A meshless natural neighbour Petrov–Galerkin method (NNPG) is presented for solving the elasticity problems in this paper. In a certain domain, a discrete model consists of a set of distinct nodes, and a polygonal description of the boundary. The natural neighbour interpolation has Kronecker delta function property, and the construction of local sub-domain is simple both for internal nodes and boundary nodes. The whole interpolation is constructed with respect to the natural neighbour nodes and Voronoi tessellation of the given point. A local weak form over the local Delaunay triangular sub-domain is used to obtain the discretized system of equilibrium equations. The numerical results show the presented method is easy to implement and very accurate, especially for solving the problems of crack propagation or large deformations.

Abstract: The Duncan-Chang nonlinear constitutive model is used to carry out a three-dimensional finite element analysis of Xia Ban Di deep overburden dam with clay core. The regularities of the horizontal displacement, vertical stress and stress level for the cut-off wall are studied in this paper, and the paper provided reference for the dam stability and anti-seepage treatment of the cut-off wall with deep overburden.

Abstract: This paper proposes a idea of microfibril preparation with physical methods. Through the design of wedge structure of experiment table and with the condition of the dynamic pressure jet putting the soften the micro wood fibers to cell wall by squeezing and shearing and torsion and so on and forming the microfibril test specimen. This paper describes the development of foreign microibrils of the status, pointing out the significance of microfibril preparation and application prospects. And to develop the corresponding technical route and to analyze the feasibility of microfibril preparation.

Abstract: License plate recognition is an important application topic of computer vision and pattern recognition technology in intelligent transportation field. Recognition system, which can automatically extract the license plate and segment the characters from an image, then recognize the characters, is a special computer vision system based on specific targets for the object. Generally, the system consists of hardware and software. In recent years, with the rapid development of LabVIEW software, LabVIEW not only has powerful data processing function, but also provides a lot of various kits. This paper is mainly to complete the functions of image preprocessing, license plate localization and license plate segmentation etc., by processing acquired image based on LabVIEW software programming.

Abstract: By using a variety of energy-saving technologies, low-grade geothermal energy will be efficiently used for improving the indoor thermal environment with few high-grade electric energy in low enthalpy geothermal engineering. In order to be more targeted and precise, geothermal energy conservation engineering should be designed and controlled on the basis of characteristics and variation of indoor thermal environment. Taking the low enthalpy geothermal engineering in the Air Force Command Academy veteran cadre living area as an example, it generalizes the building and simulates the indoor thermal environment by DeST software. The results show that the thermal enironment of rooms which are on the different storeies and different orientations is different. it is be obvious regularity, the thermal enironment of rooms in the high storey and low storey is worse than the middle storey in winter, the thermal enironment of rooms in north is worse than in south, the thermal enironment of rooms in west is worse than in east, and the thermal enironment of rooms in the corner is worse than in the middle. All of these may be a guide to equipment selection, layout of pipe network and terminal equipment, and can provide a theoretical basis for energy conservation design and operations control.

Abstract: The effect of processing temperature and strain on microstructure and mechanics property of 4032 Al alloy was performed with hot extrusion experiment and finite element method. The results show that the primary silicon distributes more uniformly along with the increase of strain at a certain deformation temperature, and the tensile stress and elongation have less variation. However, elongation decreases obviously when the strain are higher than 70%. At a certain strain, tensile strength increases and elongation decreases when deformation temperature are higher than 400 °C. Primary silicon also grows obviously. Finally, finite element calculated load data testified the experimental results.