Sn coatings were fabricated by mechanical coating technique for the first time. The coatings were characterized by XRD and SEM, among others. The SEM showed that the coatings had an irregular and uneven morphology. Th...Sn coatings were fabricated by mechanical coating technique for the first time. The coatings were characterized by XRD and SEM, among others. The SEM showed that the coatings had an irregular and uneven morphology. The influence of the rotation speed of planetary ball mill on the evolution and formation of the coatings was also investigated. The results indicated that continuous Sn coatings can be formed under a moderate rotation speed. In other words, the coatings cannot be formed when rotation speed was too high or too low. The evolution of the coatings was examined and discussed. The results showed that it followed the universal evolution law of metal coatings which included four stages. However, the exfoliation of the coatings was not seen even the milling time reached 30 h.展开更多
In this work, TiO2/Ti composite films were fabricated by 2-setp MCT and the following high temperature oxidation. Antibacterial activity of the composite films treated by ultrasonic cleaning to increase the performanc...In this work, TiO2/Ti composite films were fabricated by 2-setp MCT and the following high temperature oxidation. Antibacterial activity of the composite films treated by ultrasonic cleaning to increase the performance reliability was examined. The prepared TiO2/Ti composite films showed high photocatalytic activity in the degradation of methylene blue solution. It is obvious that? TiO2/Ti composite films have antibacterial activity under UV irradiation.展开更多
We investigated an integrated manufacturing method to develop lightweight composite materials. To design the preparation process for the integrated honeycomb plates, the shear and compressive mechanical properties of ...We investigated an integrated manufacturing method to develop lightweight composite materials. To design the preparation process for the integrated honeycomb plates, the shear and compressive mechanical properties of the corresponding composite materials were also investigated. The results indicate that these composite materials, with two types of resins reinforced by short basalt fibers, exhibit obvious toughness, particularly in their compressive properties. The Epoxy Resin （ER） is denser and has better bonding at the fiber and matrix interface than the vinyl ester resin matrix. Therefore, the ER exhibits better shear and compressive strengths than the vinyl ester resin matrix, thereby providing a design technology of the preparation process of the integrated honeycomb plate. The matrix material of this plate is composed of an epoxy （E51 ）, a curing agent （593）, and a thinner （501） at a ratio of 10：3：1; short basalt fibers are added as a reinforcing material at a 30% volume fraction. By increasing the curing temperature and other experimental conditions, we obtained an expected integrated honeycomb plate. This integrated honeycomb plate possesses properties such as a high fiber content, good shear and compressive performance, and high proc- essing efficiency.展开更多
The microstructure and thermal conductivity of four groups of Mg–rare earth（RE） binary alloys（Mg–Ce,Mg–Nd, Mg–Y and Mg–Gd） in as-cast and as-solutionized states were systematically studied. Thermal conductivi...The microstructure and thermal conductivity of four groups of Mg–rare earth（RE） binary alloys（Mg–Ce,Mg–Nd, Mg–Y and Mg–Gd） in as-cast and as-solutionized states were systematically studied. Thermal conductivity was measured on a Netzsch LFA457 using laser flash method at room temperature. Results indicated that for as-cast alloys, the volume fraction of second phases increased with the increase of alloying elements. After solutionizing treatment, a part or most of second phases were dissolved in α-Mg matrix, except for Mg–Ce alloys. The thermal conductivity of as-cast and as-solutionized Mg–RE alloys decreased with the increase of concentrations. The thermal conductivity of as-solutionized Mg–Nd,Mg–Y and Mg–Gd alloys was lower than that of as-cast alloys. Thermal conductivity of as-solutionized Mg–Ce alloys was higher than that of as-cast alloys, because of the elimination of lattice defects and fine dispersed particles during solutionizing treatment. Different RE elements have different influences on the thermal conductivity of Mg alloys in the following order： Ce 〈 Nd 〈 Y 〈 Gd. Ce has the minimum effect on thermal conductivity of Mg alloys, because of the very low solubility of Ce in the α-Mg matrix. The variations in the atomic radius of the solute elements with Mg atom（ r）, valence, configuration of extranuclear electron of the solute atoms, and the maximum solid solubility of elements in the α-Mg matrix were suggested to be the main reasons for the differences in thermal conductivity of resulting Mg–RE alloys.展开更多
文摘Sn coatings were fabricated by mechanical coating technique for the first time. The coatings were characterized by XRD and SEM, among others. The SEM showed that the coatings had an irregular and uneven morphology. The influence of the rotation speed of planetary ball mill on the evolution and formation of the coatings was also investigated. The results indicated that continuous Sn coatings can be formed under a moderate rotation speed. In other words, the coatings cannot be formed when rotation speed was too high or too low. The evolution of the coatings was examined and discussed. The results showed that it followed the universal evolution law of metal coatings which included four stages. However, the exfoliation of the coatings was not seen even the milling time reached 30 h.
文摘In this work, TiO2/Ti composite films were fabricated by 2-setp MCT and the following high temperature oxidation. Antibacterial activity of the composite films treated by ultrasonic cleaning to increase the performance reliability was examined. The prepared TiO2/Ti composite films showed high photocatalytic activity in the degradation of methylene blue solution. It is obvious that? TiO2/Ti composite films have antibacterial activity under UV irradiation.
基金the Natural Science Foundation of China under Grant 51173026 and the National Key Technologies R&D Program of China
文摘We investigated an integrated manufacturing method to develop lightweight composite materials. To design the preparation process for the integrated honeycomb plates, the shear and compressive mechanical properties of the corresponding composite materials were also investigated. The results indicate that these composite materials, with two types of resins reinforced by short basalt fibers, exhibit obvious toughness, particularly in their compressive properties. The Epoxy Resin （ER） is denser and has better bonding at the fiber and matrix interface than the vinyl ester resin matrix. Therefore, the ER exhibits better shear and compressive strengths than the vinyl ester resin matrix, thereby providing a design technology of the preparation process of the integrated honeycomb plate. The matrix material of this plate is composed of an epoxy （E51 ）, a curing agent （593）, and a thinner （501） at a ratio of 10：3：1; short basalt fibers are added as a reinforcing material at a 30% volume fraction. By increasing the curing temperature and other experimental conditions, we obtained an expected integrated honeycomb plate. This integrated honeycomb plate possesses properties such as a high fiber content, good shear and compressive performance, and high proc- essing efficiency.
基金co-supported by the National Natural Science Foundation of China (Grant No. 51474043)the Education Commission of Chongqing Municipality (Grant No. KJZH14101)the Chongqing Municipal Government (Grant No. CSTC2013JCYJC60001, Two River Scholar Project and The Chief Scientist Studio Project)
文摘The microstructure and thermal conductivity of four groups of Mg–rare earth（RE） binary alloys（Mg–Ce,Mg–Nd, Mg–Y and Mg–Gd） in as-cast and as-solutionized states were systematically studied. Thermal conductivity was measured on a Netzsch LFA457 using laser flash method at room temperature. Results indicated that for as-cast alloys, the volume fraction of second phases increased with the increase of alloying elements. After solutionizing treatment, a part or most of second phases were dissolved in α-Mg matrix, except for Mg–Ce alloys. The thermal conductivity of as-cast and as-solutionized Mg–RE alloys decreased with the increase of concentrations. The thermal conductivity of as-solutionized Mg–Nd,Mg–Y and Mg–Gd alloys was lower than that of as-cast alloys. Thermal conductivity of as-solutionized Mg–Ce alloys was higher than that of as-cast alloys, because of the elimination of lattice defects and fine dispersed particles during solutionizing treatment. Different RE elements have different influences on the thermal conductivity of Mg alloys in the following order： Ce 〈 Nd 〈 Y 〈 Gd. Ce has the minimum effect on thermal conductivity of Mg alloys, because of the very low solubility of Ce in the α-Mg matrix. The variations in the atomic radius of the solute elements with Mg atom（ r）, valence, configuration of extranuclear electron of the solute atoms, and the maximum solid solubility of elements in the α-Mg matrix were suggested to be the main reasons for the differences in thermal conductivity of resulting Mg–RE alloys.
