Applied Mechanics and Materials Vols. 184-185

Abstract: The recently researching progress on the microscopic mechanism of metal’s pure electroplastic effect is reviewed. The further research trend about microscopic mechanism of the metal’s pure electroplastic effect is pointed out.

Abstract: This paper studied how to prepare Methyl Sodium Silicate from Methyl Trichlorosilane. Methyl trichlorosilane hydrolyzed on the interface of cyclohexane and water, then hydrolysate and sodium hydroxide prepared methyl sodium silicate at molten state. Manufactrue was characterised by XRD, IR, and differential thermal analysis. The experimental results indicate that the best hydrolyze condition was the proportion of methyl trichlorosilane and water was 10~12:100 , at 5°C, lasting for 45min; the best condition of prepared methyl sodium silicate was the proportion of sodium hydroxide and hydrolysate was 2.1~2.3:1, at 300 ~450°C, lasting for 50min. The manufacture was white powder, water-solubility and well stabilization bellow 450°C.

Abstract: A relatively new method called cathodic plasma electrolytic oxidation (CPEO) was development to fabricate Al2O3–ZrO2 composite coating on AZ91 biomedical magnesium alloy. The microstructure and properties of the composite coating including phase composition, surface and cross section morphology, thickness and bonding strength were investigated. The corrosion behavior of the coated magnesium alloy in simulated body fluids(SBF) was primarily evaluated. The results showed that the coating was composed of c-ZrO2, α-Al2O3 and γ-Al2O3. The coating surface was coarse and porous with the average pores diameters of 5 µm. The thickness of the coating was about 60 µm and the bonding strength of coating to the AZ91 substrate was 22 MPa. The polarization test indicated that corrosion potential (Ecorr) and corrosion current density (icorr) of the coated samples in SBF were −1.56V and 8.89×10-7 A/cm2 , respectively, whose corrosion resistance was significantly improved compared to the uncoated sample.

Abstract: Non-quenched prehardened steel for plastic mould with 700 mm thickness (NQP700) has been developed in order to save energy and shorten the producing cycle. Microstructure and properties of the NQP700 steel are studied. The results show that microstructure of the NQP700 steel block is bainite distributing uniformly through the whole section, whose hardness fluctuation is not more than ±1.5HRC. Its polishing ability and pattern etching properties satisfy the needs of plastic mould, and it has better machinability

Abstract: PbTiO₃ crystals with different morphologies, such as flower-like and spherical shape, which was constructed by oriented nanoparticles have been obtained by a simple surfactant-free hydrothermal process assisted by K₂CO₃ as a mineralizer. Powder X-ray diffraction (XRD) analysis was applied to examine the purity and crystallinity of the as-prepared samples. The morphologies have been characterized by scanning electron microscopy (SEM). The results indicated that the self-assembly structures of PbTiO₃ crystals were dependent on the addition amount of K₂CO₃ and the formation mechanism of the products was briefly discussed.

Abstract: A series of VC/TiN nano-multilayer films with various TiN layer thicknesses were synthesized by magnetron sputtering method. The relationship between the modulation structure and superhardness effect of the multilayer films were investigated. The results reveal that TiN below a critical layer thickness grows coherently with VC layers in multilayers. Correspondingly, the hardness and elastic modulus of the multilayers increase significantly. The maximum hardness and modulus achieved in these multilayers is 40.7GPa and 328GPa.With further increase in the TiN layer thickness, coherent structure of multilayers are destroyed, resulting in a remarkable decrease of hardness and modulus. The superhardness effect of multilayers is related to the three directional strains generated from the coherent structure.

Abstract: Composite photocatalysts using TiO2 coated by Multi-walled carbon nanotues(MWCNTs) and CdS were prepared by sol-gel process. The purpose of adding MWCNTs and CdS was extending the light absorbance range of pure TiO2 to visible light. Methyl orange (MO) was chosen as an object. The degradation of MO by MWCNTs/TiO2/CdS composite photocatalysts under visible light irradiation was studied. The results showed that the presence of MWCNTs and CdS can enhance the photoefficiency of TiO2 greatly. In addition, The photocatalyst was used for five cycles with photocatalytic degradation efficiency still higher than 96%. The photocatalytic degradation of MO followed a first-order kinetics according to the Langmuir-Hinshelwood model. A possible decomposing mechanism for the photocatalytic oxidative degradation was also discussed. The results of the study showed the potential use of MWCNTs/TiO2/CdS composite in degradation of toxic organic pollutants.

Abstract: In recent years, as improvement of human living life, people begin to focus on themselves health. It is certain that bamboo charcoal has many properties, including water purification, deodorization, anion release and far-infrared ray radiation. This study aims to prepare PET/BC warp-knitted fabric composed of polyester yarn (PET) as warp yarn and bamboo charcoal polyamine yarn (BC) as weft yarn using Velcro Crochet Machine. Afterwards, air permeability, elastic resilience and far-infrared ray emissivity of resulting knitted fabric were discussed by changing weft yarn type. Result shows that, for knitted fabrics, weft yarn type cannot affect the elastic resilience; yet PET weft yarn makes air permeability decreasing.

Abstract: The dressing is used to prevent the bacterial infection when trauma is in contact with the outside air, to inhibit vivo moisture loss and then to accelerate wound healing. So the dressing nonwoven fabric needs to have good vapor permeability, comfortableness and flexibility. In addition, the far infrared fiber has ability to accelerate the wound healing. Therefore, in this research, the far infrared fiber and absorbent cotton were used to produce composite dressing fabric. By changes of blending contents of the above two fibers, the properties of dressing fabrics including vapor permeability, water absorption and flexibility were all evaluated for future application.

Abstract: Calcium phosphate bone cement (CPC), a ceramic material, is commonly used as a biomaterial for the restoration of bone injuries. This study creates the composite scaffolds by mixing CPC with various amounts of polylactide fibers. Then, the resulting scaffolds are observed and tested in terms of the morphology, compressive strength, and fiber distribution, respectively, to explore the influence of the addition of polylactide fibers on the scaffolds. According to the experimental result, the compressive strength of the scaffolds increases as a result of an increase in the addition of fibers.