A procedure of low temperature solid-phase sintering(LTSS) was carried out to fabricate sintered metal fibrous media(SMFM) with high specific surface area.Stainless steel fibers which were produced by cutting proc...A procedure of low temperature solid-phase sintering(LTSS) was carried out to fabricate sintered metal fibrous media(SMFM) with high specific surface area.Stainless steel fibers which were produced by cutting process were first plated with a coarse copper coating layer by electroless plating process.A low-temperature sintering process was then completed at about 800 °C for 1 h under the protection of hydrogen atmosphere.The results show that a novel SMFM with complex surface morphology and high specific surface area(0.2 m2/g) can be obtained in this way.The effect of sintering temperature on the surface morphology and specific surface area of SMFM was studied by means of scanning electron microscopy and Brunauer-Emmett-Teller.The damage of micro-structure during the sintering process mainly contributed to the loss of specific surface area of SMFM and the optimal sintering temperature was 800 °C.展开更多
The FeCrA1 fiber was used to prepare porous metal materials with air-laid technology, and then followed by sintering at 1300 ℃ for a holding period of 2 h in the vacuum. In addition, a novel fractal soft, which was d...The FeCrA1 fiber was used to prepare porous metal materials with air-laid technology, and then followed by sintering at 1300 ℃ for a holding period of 2 h in the vacuum. In addition, a novel fractal soft, which was developed based on the fractal theory and the computer image processing technology, was explored to describe the pore structure of porous metal materials. Furthermore, the fractal dimension of pore structure was calculated by the soft and the effects of magnification and porosity on ffactal dimension were also discussed. The results show that the fractal dimension decreases with increase in the magnification, while it increases continuously with the porosity enhancing. The interrelationship between the fractal dimension and the magnification or porosity can be presented by the equation of D=α_0exp(-x/α_1)+α_2和D=k_2-(k_1-k_2)/[1+exp((θ-k_0)/k_3)], respectively.展开更多
TiO2 fibers were prepared via alternatively introducing water vapor and Ti precursor carried by N2 to an APCVD (chemical vapor deposition under atmospheric pressure) reactor at ≤200 ℃. Activated carbon fibers (A...TiO2 fibers were prepared via alternatively introducing water vapor and Ti precursor carried by N2 to an APCVD (chemical vapor deposition under atmospheric pressure) reactor at ≤200 ℃. Activated carbon fibers (ACFs) were used as templates for deposition and later removed by calcinations. The obtained catalysts were characterized by scanning electron micros- copy (SEM), transmission electron microscopy (TEM), Brunauer, Emmett and Teller (BET) and X-ray diffraction (XRD) analysis The pores within TiO2 fibers included micro-range and meso-range, e.g., 7 nm, and the specific surface areas for TiO2 fibers were 141 m^2/g and 148 m^2/g for samples deposited at 100 ℃ and 200℃ (using ACFI700 as template), respectively. The deposition temperature significantly influenced TiO2 morphology. The special advantages of this technique for preparing porous nano-material include no consumption of organic solvent in the process and easy control of deposition conditions and speeds.展开更多
The high-temperature acoustic absorption performance of porous titanium fiber material was investigated in terms of sample thickness, porosity, temperature, air-cavity thickness and double-layer structure arrangement....The high-temperature acoustic absorption performance of porous titanium fiber material was investigated in terms of sample thickness, porosity, temperature, air-cavity thickness and double-layer structure arrangement. The effects on absorption coefficient were systematically assessed. The results show that the sound absorption performance is improved by increasing the sample porosity and/or thickness, and/or increasing the air-cavity thickness. Meanwhile, increasing the temperature gives better acoustic absorption performance in the low frequency range but also lowers the performance in the high frequency range, while double-layer structure enables better acoustic absorption performance.展开更多
基金Project (50930005) supported by the National Natural Science Foundation of ChinaProject (U0834002) supported by the Key Programof NSFC-Guangdong Joint Funds of China+1 种基金Project (LYM09024) supported by Training Program for Excellent Young Teachers withInnovation of Guangdong University, ChinaProject (2009ZM0121) supported by the Fundamental Research Funds for the CentralUniversities of South China University of Technology,China
文摘A procedure of low temperature solid-phase sintering(LTSS) was carried out to fabricate sintered metal fibrous media(SMFM) with high specific surface area.Stainless steel fibers which were produced by cutting process were first plated with a coarse copper coating layer by electroless plating process.A low-temperature sintering process was then completed at about 800 °C for 1 h under the protection of hydrogen atmosphere.The results show that a novel SMFM with complex surface morphology and high specific surface area(0.2 m2/g) can be obtained in this way.The effect of sintering temperature on the surface morphology and specific surface area of SMFM was studied by means of scanning electron microscopy and Brunauer-Emmett-Teller.The damage of micro-structure during the sintering process mainly contributed to the loss of specific surface area of SMFM and the optimal sintering temperature was 800 °C.
基金Project(2011CB610302) supported by the National Basic Research Program of ChinaProjects(51074130,51134003) supported by the National Natural Science Foundation of ChinaProject(20110491699) supported by the National Science Foundation for Post-doctoral Scientists of China
文摘The FeCrA1 fiber was used to prepare porous metal materials with air-laid technology, and then followed by sintering at 1300 ℃ for a holding period of 2 h in the vacuum. In addition, a novel fractal soft, which was developed based on the fractal theory and the computer image processing technology, was explored to describe the pore structure of porous metal materials. Furthermore, the fractal dimension of pore structure was calculated by the soft and the effects of magnification and porosity on ffactal dimension were also discussed. The results show that the fractal dimension decreases with increase in the magnification, while it increases continuously with the porosity enhancing. The interrelationship between the fractal dimension and the magnification or porosity can be presented by the equation of D=α_0exp(-x/α_1)+α_2和D=k_2-(k_1-k_2)/[1+exp((θ-k_0)/k_3)], respectively.
基金Project (No. 20477006) supported by the National Natural ScienceFoundation of China
文摘TiO2 fibers were prepared via alternatively introducing water vapor and Ti precursor carried by N2 to an APCVD (chemical vapor deposition under atmospheric pressure) reactor at ≤200 ℃. Activated carbon fibers (ACFs) were used as templates for deposition and later removed by calcinations. The obtained catalysts were characterized by scanning electron micros- copy (SEM), transmission electron microscopy (TEM), Brunauer, Emmett and Teller (BET) and X-ray diffraction (XRD) analysis The pores within TiO2 fibers included micro-range and meso-range, e.g., 7 nm, and the specific surface areas for TiO2 fibers were 141 m^2/g and 148 m^2/g for samples deposited at 100 ℃ and 200℃ (using ACFI700 as template), respectively. The deposition temperature significantly influenced TiO2 morphology. The special advantages of this technique for preparing porous nano-material include no consumption of organic solvent in the process and easy control of deposition conditions and speeds.
基金Projects(51671152,51304153)supported by the National Natural Science Foundation of China
文摘The high-temperature acoustic absorption performance of porous titanium fiber material was investigated in terms of sample thickness, porosity, temperature, air-cavity thickness and double-layer structure arrangement. The effects on absorption coefficient were systematically assessed. The results show that the sound absorption performance is improved by increasing the sample porosity and/or thickness, and/or increasing the air-cavity thickness. Meanwhile, increasing the temperature gives better acoustic absorption performance in the low frequency range but also lowers the performance in the high frequency range, while double-layer structure enables better acoustic absorption performance.