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Hot stamping represents an innovative manufacturing process for forming of advanced high strength steels, implying a sheet at austenite temperature being rapidly cooled down and formed into a die at the same time (quenching). This affords the opportunity to manufacture components with complex geometric shapes, high strength and a minimum of springback which currently find applications as crash relevant components in the automotive industry. With regard to the numerical modeling of the process, the knowledge of thermal and thermo-mechanical properties of the material is required. The material model under hot stamping condition of advanced high strength steel should be set up. The Finite Element Analysis is an essential precondition for a good process design including all process parameters. This paper presents the finite element simulation of a hot stamping process and describes a number of procedures for the simulation of hot stamping. In addition, the development direction is pointed out at the end of this paper.

Aluminum-bronze/steel duplex metal has been prepared by aluminum-bronze powder whose compact oxide film was removed by dilute HCl solution before sintering. Scanning electronic microscope (SEM), energy spectrum analysis (EDS), density measurement and compression shear strength test were used to investigate the structure, composition, relative density and bond strength of aluminum-bronze/steel duplex metal. The results show: liquid phase could wet the aluminum-bronze powder washed by acid, improve sintering activity of the powder and increase bond strength of aluminum-bronze/steel interface. The relative density of sintered aluminum-bronze is 99.6%, and shear strength of aluminum-bronze/steel interface is 132.6MPa.

Using SiO₂ – Al₂O₃ – B₂O₃ – K₂O – Na₂O system glaze as base material, adding silicon powder or alumina powder with grain size 15μm by the mass percent of 10%, 20%, 30%, respectively, melting properties of glaze were investigated. Slilica solution as binder, the anti-oxidation coating were prepared. Oxidation resistance was determined by coating to the surface of the Al2O3-C specimens. The results show that additives can raise flow temperature prominently, but has little influence on softening point and semi-sphere point; Glazing temperature ranges are obtained with different additive contents; Glazing temperature rises with addition of silicon; Glazing temperature range widens with silicon adding; Glazing temperature ranges were not strictly corresponding with softening temperature point and flow temperature point; But differences were not tremendous; glazing temperature ranges can be estimated from softening temperature point and flow temperature point. Alumina has not prominent influence on glazing temperature, but glaze forms smoothly with alumina, and oxidation resistance was good.

Zinc zeolite-Ce/ TiO₂ antibacterial material was prepared through immersion method with anatase nano- TiO₂ power as main raw materials, zinc zeolite as carrier and cerium ions as doping ions. Its antibacterial function was evaluated by detecting the inhibition zone, the light-catalyzed effect of pure TiO₂ antibacterial material was contrasted with zinc zeolite-Ce/ TiO₂ antibacterial material by using ultraviolet spectrum. The results showed that zinc zeolite-Ce/ TiO₂ antibacterial material had strong bacteriostasis to escherichia coli. It performed best when the diameter of inhibition zone reached to 34.64 mm under the condition of the ratio of nano-TiO₂ to cerous nitrate was 40:1, the reacting time was half an hour, the maturing temperature was 300°Cand pH value was equal to 3.

A new BCB (Bamboo Charcoal Bonded) grinding wheel was developed by bamboo charcoal-phenolic resin composite under vacuum for ELID grinding technology. The pyrolysis behavior of the new bamboo charcoal-phenolic resin material was studied by thermo gravimetric analysis (TGA), and structural characterization of the new material was performed by scanning electron microscopy (SEM), X-ray diffraction (XRD), the friction characteristics was also investigated in this paper.

The relationship between heat treatment processes and grinding performance of cold die steel 9Mn2V had been built in this paper. Serious meshy segregation of carbide, excessive amounts of retained austenite, coarse and inhomogeneous distribution of material structure were significant causes of grinding burn and grinding crack. In order to improve the abrasion-resistance and mechanical properties of workpiece material, cryogenic and tempering treatment were added. Disappear of meshy segregation of carbide, network carbide was within second grade, retained austenite content was within 4%, martensite became much more fine and homogeneous, all of these advantages could be obtained by adopting cryogenic and tempering treatment in twice. The grinding experiment results indicated that workpiece material 9Mn2V which using this process could provide superior grinding performance.

In this paper, numerical simulation technology was applied to comprehensively analyze and study the mechanical properties of the derrick. The three-dimensional finite elements analysis model of the derrick structure was established, which provided the physical model of the numerical simulation and the optimization of the three-dimensional derrick. The finite element simulation method was applied to analyze and optimize the mechanical and deformation of the three-dimensional derrick structure, so that the theoretical method to study and design the three-dimensional derrick using finite element method was established.

Colored binder was prepared by mixing aromatic oil with petroleum resin and functional polymers. Then the colored binder combined with pigment, aggregates, and additives resulted in colored asphalt mixture. Futher modification by nano-montmorillonite or coupling agent, higher pavement performance was chieved. The paving technical indexes of the mixture such as physical properties, moisture susceptibility, and high temperature stability were tested. The results demonstrate that the high temperature stability and moisture susceptibility can be satisfied with the requirements of hardscape projects including asphalt driveways, asphalt walkways, asphalt streets, asphalt bike paths, and asphalt walking paths.

Detecting community structure from complex networks has triggered considerable attention in several application domains. This paper proposes a new community detection method based on improved genetic algorithm (named CDIGA), which tries to find the best community structure by maximizing the network modularity. String encoding is used to realize genetic representation. Parts of nodes assign their community identifiers to all of their neighbors to ensure the convergence of the algorithm and eliminate unnecessary iterations when initial population is created. Crossover operator and mutation operator are improved too, one-way crossover strategy is introduced to crossover process, the Connect validity of mutation node is ensured in mutation process. We compared it with three other algorithms in computer generated networks and real world networks, Experiment Results show that the improved algorithm is highly effective for discovering community structure.

Aiming at avoiding misregistration in complicated medical image registration based on SURF (Speed-Up Robust Features)-TPS (Thin-Plate Spline), we propose a novel algorithm. This method is based on SURF and human interaction method for feature extraction. Then we improve SURF-TPS and propose an algorithm named TPS-SEMISURF which obtains the deformation field by calculating the Thin-plate spline of the feature points, and finally does the medical image non-rigid registration according to the parameters. Experimental results showed that the proposed method can register medical images effectively. It has a good robustness and owns better precision and rate than traditional algorithm.