Advanced Materials Research Vols. 287-290

Abstract: Representative volume element methord is used to simplify HGB (hollow glass bead) periodically-reinforced composite model into representative volume element. Orthotropic properties and change rules of effective elastic constants (modulus and Poisson's ratio) and HGB wall-thickness of representative volume element are studied by using the finite element methord. The study finds that there is no obvious difference of each direction of the three kinds of composites with different filling types; the effect of filling type is not very obvious also.

Abstract: The effect of electromagnetic field on the solidification structure of C70250 copper alloy (Cu-3.2%Ni-0.8%Si in mass%) had been investigated in this paper. The results show that applying electromagnetic field during the solidification of C70250 copper alloy can refine as-cast structure and δ-Ni₂Si phase. The morphology of δ-Ni₂Si phase changes from coarse massive shape to fine dotlike shape. The above-mentioned effects become more obvious with the increasing in current intensity.

Abstract: Functional nonwoven products have superiority such as quick mass-production, short processing time, wide sources for raw material, low cost and high output etc. They have been widely studied and promoted in advanced countries. However, comparing with selvedge processing, they brings considerable burden to environment. So in this paper, we chose low cost polyester (LPE) and low melting point fiber (LMPE) respectively blending by 50 wt% through the process of mixing, blowing, carding, laying, and needle punching etc. to form nonwoven fabric in which the needle density was adjusted. Finally it is found that 103 needles/cm2 was optimal after mechanical testing. And then different proportions of PP selvedges were placed in the middle of two optimal nonwoven layers by sandwich structure, and mechanical properties of PET/LMPET/PP fabric produced after thermo bonding and cooling was tested. According to the optimal production evaluation for functionality, these products may apply to reinforced interlayer in general protective clothing, protective glove, reinforcement in simple building structure and stiffening geotextiles in the future.

Abstract: A method to obtain welding deformation values and simulating welding deformation effect is proposed in the paper. In this method, the structure is subdivided into Triangular element, the coordinates for nodes adopt the actual value, the coordinates of points are calculated with interpolation of all nodes in the element, and the normal vector of node is expressed with the average value of normal vectors from all elements related. Experiments show that the new method is effective to simulate the welding deformation, and has great practical significance.

Abstract: In this paper, the advantages of smart materials and structures are introduced. Because of the influence of friction, it’s difficult to deploy the large ring truss antenna driving by cable. The SPMC hinge is added in the deployable joint, the deployable antenna is deployed by heating the material to cause recovery strain, which substitutes for the driving by cable. Describe the behavior of SPMC material, and do the simulation, from the analysis results, we can aim that the stress of SPMC satisfies the yielding stress when the node is furled. At the same time, the force to expand the antenna caused by heating SPMC is also obtained. Compared the different size of width, the variation of recovery force can be got.

Abstract: This paper discusses the realization of the cascade of two stage rotary coder. It is aimed to establish a coordinate system to apply in the continuous and precision measurement of the displacement and rotary angle in a large scale. This coordinate system can be used for any industrial control process in which there are particular demands for the measurement of the displacement and rotary angle. It has characteristics of high resolution, large scale and non-volatile.

Abstract: Dynamic performance of a water hydraulic piston pump with flat valves was analyzed．Its mathematic model was established and influence factors were studied by simulation. The results show that reducing clearance volume, lighting spool quality and increasing spring stiffness are favorable to promote the performance of flat valve. In addition, higher vacuum degree and too high rotational speed will make flat valve delay more seriously. Work pressure also has influence on the opening delay to flat valve．

Abstract: The fluid flow in the mould of slab continuous caster was investigated by 1:1 ratio water modeling simulation system. The effects of outlet angle of Bilateral and quadripuntal SEN on surface turbulence, penetration depth and surface velocity were discussed and the regularity of the flow field for change of outlet angle in slab continuous casting mould was obtained. The results show that the case C (both α and β are downward angle and α<β) is better than the usual SEN, for this kind of SEN can stabilize surface turbulence and reduce penetration depth and get moderate velocity.

Abstract: This paper designs a resonant diaphragm liquid density sensor. From the reality, a resonant diaphragm is designed and manufactured. Processing technology on resonant diaphragm is studied and improved through compensating elastic error, and eliminating residual stress. Incentive coil is designed using the eddy current effect.

Abstract: Structural health monitoring of RC structures under seismic loads has recently attracted attention in the earthquake engineering research. In this paper, a piezoceramic-based device called “smart aggregate” was used for the health monitoring of RC frame structures under earthquake excitations. A two-story one-bay RC moment frame instrumented with smart aggregates was tested using a shake table. The distributed piezoceramic-based smart aggregates embedded in the RC structures were used to monitor the health condition of the structures during the tests. The sensitiveness and effectiveness of the proposed piezoceramic-based approach were investigated and evaluated by analyzing the measured responses.