Applied Mechanics and Materials Vols. 727-728

Abstract: Microwave has been applied to ignite the Self-propagating High-temperature Synthesis (SHS) of compacted Ni-Al mixtures, having 1:1 atomic ratio, in order to join Chemical Vapor Deposition (CVD) SiC ceramics and SiC/SiC composites. The average joint thickness of CVD SiC joint is about 200 μm and the Coefficient of Thermal Expansion (CTE) mismatch between CVD SiC and Ni-Al intermetallic compounds results in a interface bond strength inferior to that of the substrate and joining material; on the other hand, for the SiC/SiC composite joints, as a result of the porosity of SiC/SiC composites, the SHS products readily infiltrated into the pore spaces of the composite, leading to an increased porosity of the joint area and a better lower interface than the upper one. The mechanical strength of the joints has been evaluated by Single-Lap (SL) shear test at room temperature; neither of the ceramic joints nor the composites joint gave satisfactory results, but the ceramic joints reaching a maximum shear strength value of 56MPa exhibited a positive aspect for further experiments.

Abstract: Novel pHsensitive methacrylate-based (co)polymers with pendent tertiary amine groups were prepared by free radical polymerization of monomer 2-(dimethylamino)ethyl methacrylate (DMA) and 2-(Dibutylamino)ethyl methacrylate (DBA). These polymers are pH sensitive in aqueous solution, which was studied by titration, transmittance measurements experiment. The pH responsive polymers dissociate at lower pH value because of the electrostatic repulsion and aggregate above their pH responsive value induced by hydrophobic interaction of pendent group. The pH responsive value of (co)polymers can be controlled by ratio of DMA and DBA. These novel polymers have great potential application for biomedicine.

Abstract: Low price of potato starch as a wide range of sources of edible film substrate, glycerol as a plasticizer, pullulan as a film-forming agent, prepared by solution casting of potato starch-based edible environment-friendly packaging materials. Tests were run on potato starch-based edible films to determine mechanical properties, transparency and color evaluation. It was observed that the increase of the glycerol content in the films increased the macromolecular mobility, the potato starch films became less stiff and more flexible. Meanwhile the transparency and yellow index are both increased, obviously.

Abstract: The preparation of polyvinyl alcohol fibers mainly consists of three steps: 1. The polymerization of vinyl acetate. Need the preparation of vinyl acetate and polymerization of vinyl acetate. The polymerization of vinyl acetate uses acetylene method and ethylene method.2. Preparation of PVA. Mainly to let the polyvinyl acetate taking alcoholysis reaction to the effect of methanol or sodium hydroxide. 3. Preparation of polyvinyl alcohol fiber. Complete dope preparation through washing and dehydration, dissolving, mixing, filtering and deaeration, and uses the dry, wet two methods to form the spinning. Finally, through the follow-up processing, to accomplish the preparation of polyvinyl alcohol fiber. Water soluble and high concentration polyvinyl alcohol fiber ‘s performances are fine and is application widely.

Abstract: To promote the application process of compacted graphite cast iron in non-automotive industry, cored wire re-sulfurization injection was developed for the production of compacted graphite cast iron. Firstly, ductile cast iron was produced by cored wire injection. Then, the effective final residual Mg level was reduced to the appropriate range for compacted graphite formation by feeding sulfidizing cored wire containing 99% S. In this paper, the influencing factors on percentage of compacted graphite were analysed, such as the final residual Mg level, cored wire injection speed. The results show that compacted graphite cast iron with less than 20% nodularity can be produced steadily on the condition of adopting the correct speed and the added sulfidizing cored wire in the range from 0.8m/t to 0.9m/t. Practice has proven that cored wire re-sulfurization injection would be most appropriate for jobbing foundries intending to manufacture compacted graphite cast iron castings for engineering industries.

Abstract: 10mm thick aluminum alloys 5A02 plates were welded using MIG beam in this paper.The MIG weld formation and microstructure morphology were studied,the hardness in the weld were measured, the tensile test were made.The test result shows that the cooperation of welding current,speed and root gap can lead to perfect welds.There are equiaxed grain in the central welds and cloumnar grain structure near the fusion line.The maximum hardness is in the fusion zone of joints,and the minimum is in the softening zone.

Abstract: Detection of ultra-weak bioluminescence for freshness of corn is not only a problem of corn safe storage but also related to corn quality. The paper built a Virtual Instrument platform based on LabVIEW and PXI4220 modularized hardware of NI. Then, a testing and analysis system for corn ultra-weak bioluminescence features was designed. Different freshness corns were tested and analyzed about the relation of freshness and ultra-weak bioluminescence features. The experimental results shows that the ultra-weak bioluminescence voltage peak values of different freshness corns all maximize about 1 hour, and voltage peak values between different freshness corns have no evident relationship. However, the ultra-weak bioluminescence voltage energy sum of different freshness corns increase progressively with the freshness degree. So, detection of voltage energy sum of different freshness corns can reflect wheat freshness effectively. Comparing with traditional method, the freshness detection method based on wheat ultra-weak bioluminescence features can realize precise, rapid and nondestructive examination.

Abstract: Through experimental study on the role of the free abrasive in chemical mechanical polishing, in this paper, four different types of abrasive which were chosen were used for the research of material removal rate(MRR) and surface quality of SiC single crystal . Finally ,Diamond abrasive which is considered was the most suitable for chemical mechanical polishing(CMP) abrasive of SiC Crystal Substrate. With diamond Particle polish pad polishing, it is draw a comparison result on the influence of the free abrasive and consolidation abrasive for the material removal rate and surface quality of 6H-SiC. The results showed that: the MRR is 140nm / min, the material removal rate if fixed abrasive chemical mechanical polishing(FA-CMP) more than three times that of traditional CMP, fixed abrasive chemical mechanical polishing pad, are involved in a large proportion of micro abrasive cutting, can greatly improve the material removal efficiency. And results from the test procedure, the FA-CMP surface has scratches after more technical problems for the polishing pad, the surface damage is relatively free of abrasive chemical mechanical polishing is more serious.

Abstract: The tensile strength, elognation and microstructure of alloy are respectively tested and observed after annealing treatment. The results show that the working rate the larger, the initial recrystallization temperature the lesser. The proper middle annealing process of Cu-Ag alloy with 80% deformation is 405°C×5h.

Abstract: The tensile strength, elongation and microstructure of alloy are respectively tested and observed after annealing treatment. The results show that the working rate the larger, the initial recrystallization temperature the lesser. The proper middle annealing process of HSn88-1 alloy with 80% deformation is 460°C×5h.