Advanced Materials Research Vols. 960-961

Abstract: Rare earth Y、Gd、Nd were added to improve the tensile strength, elongation, hardness and microstructure of AZ91D magnesium alloy in this study. The investigation had been undertaken by 8 GWU type resistance furnace, RGM - 50 electronic machine , Vickers ,etc. Results show that a moderate amount of composite adding rare earth can effectively improve the tensile strength of AZ91D alloy, elongation, hardness and the organizational structure, as a rare earth content increased after the first performance decline. When rare earth content is 1.8%, the highest tensile strength up to 276.58mpa, 8.3% elongation. When rare earth content is 2.4%, the hardness is up to 99.36 HV1.96.

Abstract: Available nanosilica commercially was modified with silane coupling agent A-151, and then emulsion was synthesized with modified SiO₂, vinyl acetate, methyl methacrylate and butyl acrylate by polymerization reaction. Effects the amount of emulsifier, initiator and organic nanoSiO₂, etc factors on the performance of emulsion polymerization and latex film were investigated. The best test results of composite emulsion of SiO₂ and vinyl acetate-acrylate were obtained by theoretical research and experimental operation: modified nanoSiO₂ content of 3%, the content of 3% emulsifier OP, content of 0.5% potassium persulfate initiator.

Abstract: Qarham to Golmud expressway is the first high-grade road in Qarham salt lake, which is regarded as the most enormous inland salt lake in China, moreover, it is the first expressway built on the inland salt lake in China. There is high and excessive saline soil distributed over this area whose thickness is no less than 20m, but the average subgrade height of the expressway is only 2m. A great many of measures are taken for the construction of the subgrade to prevent salt migrating from foundation to roadbed and pavement, which will cause disasters of secondary salinization in roadbed and pavement. By paving testing road at the site and detecting the efficiency of the measures in preventing salt, the paper put forward the technique of preventing subgrade from salinization for Qarham to Golmud expressway. The results of testing and detecting demonstrate that the height of salt migration is only 45cm in subgrade under the condition of brine supply, which is less than the height of subgrade. So it is efficient to keep the roadbed and pavement from the erosion of salt; The settlement of road surface was about 0~2mm among 3 months since the highways had been opened to traffic for two years, and uneven settlement and other diseases caused by the secondary salinization were not appeared, which showed that the measures of salinization prevention (salt resistance) were taken well to achieve the design purposes.

Abstract: Electroforming technology is an important part of micro fabrication andfine parts and composite materials prepared by the electroforming technology has broad application prospects. This paper describes the principle and method of electroforming, introduces the development and the basic elements of electroforming, then concludes the research status and main research direction and trend of this technology.

Abstract: In order to develop new protective materials for magnesium alloy, Al-based alloys with different Si-content were fabricated by copper mold casting. Microstructure, erosion properties of the ingot samples were characterized or tested by using spectrum analysis, optical imcroscope, salt testing machine etc, respectively. The results indicated that the microstructure of Al-1.9Si-1.32Mg-0.40Mn was mostly dendritic crystal. That of Al-13Si consisted of α-Al, flaky eutectic silicon and primary crystal silicon. That of Al-18Si-0.01%P was consistent of a large proporation of primary crystal silicon phase, a part of eutectic silicon phase and a little of α-Al phase. With Si-content increasing, anti-corrosion properties of Al-based alloy gradually improved, which could provide theoretical principle to determine chemical elements of protective materials for magnesium alloy.

Abstract: With the ‘Synergistic Effects’ such as ‘Bridging’ and ‘Intercalating’ between fillers with different morphologies, we can get the CF/CNTs/NanoG filled polyacrylate electrically conductive adhesives (ECA). Through the study, we found that the comprehensive properties of the electrically conductive PSA reach the best when the composite fillers are made up of CF 3wt%、NanoG 5wt% and CNTs 5wt%. The conductivity of the electrically conductive PSA reaches 3.0×10^-2 S/cm, the 180^o peel strength is 0.38KN/m and the shear strength is 0.42MPa.

Abstract: This paper studies extract as corrosion inhibitors extracted from garlic. The IR spectrum analysis of the extract shows that the main ingredient of extract is amino acids, and the better extracting condition is that 30°C50mL 10%H₂SO₄and 20g peeled garlic react for 120.0h, and composite amino acids content in the extract is 19.0mg/L. The result of corrosion inhibition performance using static weight loss shows that the dosage of the extract, temperature and concentration of acidic mediums have effect on corrosion inhibition remarkably. The corrosion inhibitive efficiency for A3 steel is 93.26% in 5% Hydrochloric acid and 79.2% in5% mud acid when the dosage of the garlic extract is 4.0%(V/V) and 6.0%(V/V),respectively. The investigated results of electrochemistry performance of the extract indicates that corrosion potential of A3 steel shift in negative direction both in Hydrochloric acid and in mud acid, which indicates that the extract are inhibitors of inhibiting cathodic corrosion, and circular-arc radius of alternating-current impedance spectroscopy increase notably in acidic medium, and corrosion inhibition effect is remarkable. Therefore, it is feasible to extract inhibitors from garlic.

Abstract: In this research, nanopore composite had an effect on enhancing thermal property and mechanical property. The nanopore composite maintained the pore structure and enhanced mechanical property. Al₂O₃ xerogel was collapsed after heat treatment over 1000°C and they had weak mechanical strength because of pores. For maintenance of pore at high temperature and improvement of mechanical strength, Al₂O₃ whisker was hybridized. The Al₂O₃ whiskers in nanopore composite play the role of pillar during heat treatment. The mechanical property of Al₂O₃ xerogel was improved through complexation with Al₂O₃ whisker. The elastic modulus of nanopore composite increased 225 % from Al₂O₃ xerogel.

Abstract: In this work, corrosion inhibition in steel water pipes, used in Shengli oilfieldis studied in different corrosive media by adsorption of dithiocarbamate (DTC) on the surface of the pipes. Electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR) and potentiodynamic was applied to determine the effection of this dithiocarbamate. And the result shows that this dithiocarbamate has high corrosion inhibition up to 90%.

Abstract: Malonate ethyl ester of butene in the presence of sodium hydroxide was synthesized by addition reaction of 2-methyl propane-1,1,3 tricarboxylic acid ester, by hydrolysis decarboxylation heatingβ-methyl glutaric acid. First with excess of methanol into methyl metaplasiaβ-methyl dimethyl glutarate, and then itsβ-methyl glutaric acid methylation, get high yield of monomethyl β-methylglutarate.