Applied Mechanics and Materials Vol. 189

Abstract: As-cast AM60 magnesium alloy was solid dissolved with exercising different pressures (atmospheric-pressure, 3, 4 and 5 Gpa) to it and subsequently aged for 10 h at 200 °C under atmospheric-pressure. The aging alloys were characterized by optical microscope, and their compressive properties were investigated by a Gleeble-3500 hot-stimulation machine. The results show that, compared with exercising atmospheric-pressure during solution treatment, exercising high-pressure during this process causes that the α-Mg grains of the subsequent aging alloy are more fine and uniform, while the β-Mg17Al12 phases transform into fine particles and aggregate to form gobbets or strips. With increasing the pressure gradually, the compressive strength of the aging alloy increases up to 4 Gpa and then decreases, while the maximum plastic strain decreases up to 4 Gpa and then increases.

Abstract: Forming process of AZ31B magnesium alloy cup parts in pressure-lubricating deep drawing was simulated by Dynaform at room temperature. The technological parameters which influence the wall thickness difference of cup parts were investigated in this paper, including internal pressure, blank holder force and punch corner radius, etc. Compared with the deformation behaviors of magnesium alloy in mechanical deep drawing and pressure-lubricating deep drawing, the wall thickness distribution of cup parts was discussed. The result shows that preferable deformation behaviors can be obtained in pressure-lubricating deep drawing when adopted adaptive technological parameters.

Abstract: Mechanical alloying (MA) and subsequent solid sintering process was used to prepare the Pr-containing pseudobinary Tb_0.7Pr_0.3Fe_1.80 alloys. The structural and magnetoelastic properties were in comparative investigated by means of x-ray diffraction and a standard strain technique for sinter and composite samples. The high Pr-content (Tb,Pr)Fe₂ Laves phase with MgCu₂-type structure for the composition Tb_0.7Pr_0.3Fe1.80 were synthesized by MA plus annealing at 500 °C.

Abstract: Effect of antimony on the microstructure, especially on the morphologies of rare earth-enriched phases, of mischmetal -containing AZ31 alloy was studied. The results showed that, by the addition of 0.8%Sb, the rare earth-enriched phases in AZ31-1.0％MM were transformed to dispersive tiny sphere-like Al-rare earth-Sb phases from coarse needle-like Al-rare earth phases. Meanwhile, rare earth-enriched phases transferred into α-Mg crystal grains from grain boundaries. On the other hand, the distribution of β-Mg17Al12 phases became more dispersive.

Abstract: The cold-rolling cladding process of composite aluminum alloy foil for automobile heat exchanger was investigated, as well as the effects of percentage reduction of first pass, clad sheet thickness and final annealing schedule on the microstructure and properties of the foil. The results showed that bonding the clad sheets A4045 to the core material A3003 on both sides succeeds initially when the percentage reduction is 30%~50% of first pass during cold rolling, and the thickness of both the clad sheets of the composite foil are basically the same. The best sagging resistance is available when the percentage reduction of final pass is 25%~35%. The annealing temperature should be controlled in the range from 320 to 400°C before finish rolling, and the annealing time should control within 80 minutes when annealed at 400°C.

Abstract: Using direct-current (DC) and pulsed double-excitation cathode arc plasma technique, diamond-like carbon (DLC) bilayers with nano-scaled interlayer of Cu and Ti were synthesized on silicon substrate. The effect of interlayer on the structure, morphology and mechanical properties of bilayer films were investigated. The change in bilayers structure occurred during interlayer introduction and greatly affected the hardness and internal stress of bilayers. Interlayer nature changed the microstructure of bilayers that in the thickness and element content of diffusion layer. Ti/DLC bilayer exhibited a similarly morphological character to DLC monolayer, whereas Cu interlayer in DLC films leaded to a formation of nanostructured surface and lower root mean square roughness due to the absence of Cu-C bond.

Abstract: Layered AlPO4-5 molecular sieve was synthesized in polyacrylamide (PAM) hydrogels. The sample was produced using synthesis gel with weight composition of 1.0Al2O3 : 1.8P2O5 : 1.2 triethylamine (TEA) : 18.0H2O : 2.2 acrylamide (AM). The synthesized layered AlPO4-5 molecular sieve had an average thickness of 2.5 μm, and each layer was approximate circle with an average diameter of 5 μm.

Abstract: Based on the index of water content, the influence of the dosage of glutaraldehyde, the mass ratio of polyvinyl alcohol(PVA) and alginate(NaAlg), the concentration of CaCl2, and the reaction time on PVA-alginate-Ca was discussed. It can be found that when the dosage of glutaraldehyde is 0.85%, the mass ration of PVA increases to 8:1, the solution quality score of CaCl2 is 2%, and the reaction time of PVA-alginate-Ca is 1.5h, the composite polymer water content reaches the highest.Then the preparation condition for PVA-alginate-Ca will be optimized by an orthogonal experiment design, and the optimum preparation condition will be found: ω (glutaraldehyde) is 0.85%, m（PVA）:m（NaAlg）is 8:1 andω(CaCl2)is 2.0%.

Abstract: A series of ferrocene schiff bases derived from Thiadiazole have been synthesized and characterized by IR, 1H NMR, and elemental analysis, the results conformed well with expected structures. The synthesized compounds were screened in vitro for their antibacterial activity against three Gram-negative (Escherichia coli, Pseudomonas aeruginosa, and Salmonella typhi) and two Gram-positive (Bacillus subtilis and Staphylococcus aureus) bacterial strains. The results showed that these compounds are a series potential new drugs in antibacterial activity against one or more species.

Abstract: Lithium titanate was poor conductive materials, this disadvantage limited its commerical use in high current applications for future hybrid electric vehicles. Li4Ti5O12/C has been examined in order to improved the electronic conductivities. We selected polyvinyl alcohol (PVA) as the carbon source to synthesize Li4Ti5O12/C composite. Different PVA additions at m(PVA)/m(Li4Ti5O12) = 5%, 10%, 15% were investigated along with the structure and electrochemical performances. The addition of PVA with a amount of 5% and 10% whould significantly improved electrochemical performance of Li4Ti5O12. When charged at 0.5 C rate, both of the samples could maintain an initial reversible capacity of about 146 mAh/g and 159 mAh/g.