2005 Vol. 20 No. 2
2005, 20(2): 1-4,12.
DOI: 10.19515/j.cnki.1003-1545.2005.02.001
Abstract：
Rotating-beam fatigue tests of 07Cr12NiMoVNb steel were carried out at room temperature and 550℃. The results indicated that the damage behavior of the steel samples with different grain size is similar. The relation between room temperature fatigue strength and ordinary tensile strength is in accordance to ojuger's experiential formula. High-temperature fatigue strength is related to ordinary tensile strength, but the linear coefficient is different from that of room temperature fatigue. Grain size has less influence on fatigue strength at room temperature. Yet at 550℃, the steel with fine grain exhibits higher fatigue strength which is contrary to creep behavior. For creep behavior, the steel with roase grain exhibits higher strength.
Rotating-beam fatigue tests of 07Cr12NiMoVNb steel were carried out at room temperature and 550℃. The results indicated that the damage behavior of the steel samples with different grain size is similar. The relation between room temperature fatigue strength and ordinary tensile strength is in accordance to ojuger's experiential formula. High-temperature fatigue strength is related to ordinary tensile strength, but the linear coefficient is different from that of room temperature fatigue. Grain size has less influence on fatigue strength at room temperature. Yet at 550℃, the steel with fine grain exhibits higher fatigue strength which is contrary to creep behavior. For creep behavior, the steel with roase grain exhibits higher strength.
Abstract：
Charpy impact test, in which specimens were cut out from the surface and center of plate, is empoloyed to investigate the effect of center segregation on continuous casting 10CrNi3MoV steel plate and its HAZ at various temperatures.The results show that center segregation deteriorates the impact property of center and the impact value of center specimens are lower than that of the surface specimens, on the other hand,there is a trend that the decrement of the impact value increase as the test temperature dropping.
Charpy impact test, in which specimens were cut out from the surface and center of plate, is empoloyed to investigate the effect of center segregation on continuous casting 10CrNi3MoV steel plate and its HAZ at various temperatures.The results show that center segregation deteriorates the impact property of center and the impact value of center specimens are lower than that of the surface specimens, on the other hand,there is a trend that the decrement of the impact value increase as the test temperature dropping.
2005, 20(2): 8-12.
DOI: 10.19515/j.cnki.1003-1545.2005.02.003
Abstract：
The precipitation of copper in high strength SMAW weld metal (contain Cu 1.48%) was investigated by use of TEM. It is manifested that in single pass weld metal there are no copper precipitations, but in heat affected zone there are some ε-Cu precipitations and the distribution and size of the precipitations are not uniform.
The precipitation of copper in high strength SMAW weld metal (contain Cu 1.48%) was investigated by use of TEM. It is manifested that in single pass weld metal there are no copper precipitations, but in heat affected zone there are some ε-Cu precipitations and the distribution and size of the precipitations are not uniform.
Abstract：
In this paper, the long term stability of porous media based phase-changing composites is investigated by means of fourier transformation infrared spectrum analysis (FTIR). The infrared spectra of lauric acid contained in the phase-changing composites that underwent more than one year of phase-changing cycles were tested and analyzed in comparison with those of sodium laurate and pure lauric acid which did not undergo any phase-changing cycle. The results show that all absorption peaks of the functional groups and chemical bonds of lauric acid still exist, which suggests that the chemical structure of lauric acid did not change after such a long time of phase-changing process in porous media. So it is concluded that the lauric acid, as organic phase-changing material, is chemically compatible with the porous media, and the phase-changing composites have long term chemical stability.
In this paper, the long term stability of porous media based phase-changing composites is investigated by means of fourier transformation infrared spectrum analysis (FTIR). The infrared spectra of lauric acid contained in the phase-changing composites that underwent more than one year of phase-changing cycles were tested and analyzed in comparison with those of sodium laurate and pure lauric acid which did not undergo any phase-changing cycle. The results show that all absorption peaks of the functional groups and chemical bonds of lauric acid still exist, which suggests that the chemical structure of lauric acid did not change after such a long time of phase-changing process in porous media. So it is concluded that the lauric acid, as organic phase-changing material, is chemically compatible with the porous media, and the phase-changing composites have long term chemical stability.
Abstract：
The structure and dielectric properties of (Bi1.5Zn0.5)(Ti1.5Nb0.5)O7-based ceramics with Bi3+ substituted by La3+ were investigated.(Bi1.5-xLaxZn0.5)(Zn0.5Nb1.5)O7samples were prepared by conventional method.The X-ray diffraction and SEM were used to analyze the microstructure.The La-doped samples held primarily pyrochlore single-phase on the whole field, and its stable range was determined by the tolerance factor (RA/RB values).With the increase of amount of La3+ substitution, crystal cell parameters showed a trend from ascent to descent.The dielectric properties varied with the microstructure.The dielectric properties of BLZNT-x samples exhibited as:ε=130~170,tanδ=0.35-0.9×10-3at 1 MHz,and the frequency characteristics at high end (＞100kHz) were optimized through the La-doping.
The structure and dielectric properties of (Bi1.5Zn0.5)(Ti1.5Nb0.5)O7-based ceramics with Bi3+ substituted by La3+ were investigated.(Bi1.5-xLaxZn0.5)(Zn0.5Nb1.5)O7samples were prepared by conventional method.The X-ray diffraction and SEM were used to analyze the microstructure.The La-doped samples held primarily pyrochlore single-phase on the whole field, and its stable range was determined by the tolerance factor (RA/RB values).With the increase of amount of La3+ substitution, crystal cell parameters showed a trend from ascent to descent.The dielectric properties varied with the microstructure.The dielectric properties of BLZNT-x samples exhibited as:ε=130~170,tanδ=0.35-0.9×10-3at 1 MHz,and the frequency characteristics at high end (＞100kHz) were optimized through the La-doping.
2005, 20(2): 20-22.
DOI: 10.19515/j.cnki.1003-1545.2005.02.006
Abstract：
The effect of fluoride on melting point,viscidity, surface tension, mobility of alkaline slag and electric arc stability was investigated through changing the kind and the amount of fluoride powder in the flux core.The effect of fluoride on diffusible hydrogen in welding seam were detected and analyzed with the liquid law.
The effect of fluoride on melting point,viscidity, surface tension, mobility of alkaline slag and electric arc stability was investigated through changing the kind and the amount of fluoride powder in the flux core.The effect of fluoride on diffusible hydrogen in welding seam were detected and analyzed with the liquid law.
2005, 20(2): 23-27.
DOI: 10.19515/j.cnki.1003-1545.2005.02.007
Abstract：
For many years, Titanium nitride (TiN) is the most generally used film in every field of applications. Another transition metal Zirconium (Zr), which belongs to the same periodic element group as Ti, is also an attractive material. There have been a lot of research reports with regard to Zirconium nitride (ZrN). However, knowledge on Zirconium carbonitride (ZrCN) is still limited. This paper presents initial experimental results on ZrCN films obtained using an unbalanced magnetron sputtering system. The main purpose of this study is to understand the effects of flow ratio of the reactive gas, nitrogen gas/acetylene (N2/C2H2), and Ti and W additives on the hardness and wear performance of ZrCN series of films. The results showed that the hardness and wear performance of ZrCN films increased with decreasing N2/C2H2 ratio when the amount of reactive gas flow rate was kept constant. The addition of Ti and W led to a significant enhancement in wear performance of ZrCN film, as well as its hardness. The enhancement by Ti additive was greater than that by W additive. ZrCN, with and without Ti/W additives, showed much better wear behavior than TiN.
For many years, Titanium nitride (TiN) is the most generally used film in every field of applications. Another transition metal Zirconium (Zr), which belongs to the same periodic element group as Ti, is also an attractive material. There have been a lot of research reports with regard to Zirconium nitride (ZrN). However, knowledge on Zirconium carbonitride (ZrCN) is still limited. This paper presents initial experimental results on ZrCN films obtained using an unbalanced magnetron sputtering system. The main purpose of this study is to understand the effects of flow ratio of the reactive gas, nitrogen gas/acetylene (N2/C2H2), and Ti and W additives on the hardness and wear performance of ZrCN series of films. The results showed that the hardness and wear performance of ZrCN films increased with decreasing N2/C2H2 ratio when the amount of reactive gas flow rate was kept constant. The addition of Ti and W led to a significant enhancement in wear performance of ZrCN film, as well as its hardness. The enhancement by Ti additive was greater than that by W additive. ZrCN, with and without Ti/W additives, showed much better wear behavior than TiN.
2005, 20(2): 28-32.
DOI: 10.19515/j.cnki.1003-1545.2005.02.008
Abstract：
A waterborne polyaniline microlatex is synthesized by a new modified microemulsion polymerization and the resulting microlatex could be applied as a coating for metal protection without further demulsification. A waterborne metal corrosion-resistant coating with good performance has been assembled using a mixture of the polyaniline microlatex with an epoxy emulsion as a prime coating, and a pure epoxy emulsion as a surface coating. The composite coating could enhance the open-circuit potential of a mild steel panel to circa 235mV comparing with that of the bare ones. They have not become blistered or rusted when they are exposed in tap-water for at least 3 months. It is indicated that the polyaniline microlatex is a sort of environmental friend coating.
A waterborne polyaniline microlatex is synthesized by a new modified microemulsion polymerization and the resulting microlatex could be applied as a coating for metal protection without further demulsification. A waterborne metal corrosion-resistant coating with good performance has been assembled using a mixture of the polyaniline microlatex with an epoxy emulsion as a prime coating, and a pure epoxy emulsion as a surface coating. The composite coating could enhance the open-circuit potential of a mild steel panel to circa 235mV comparing with that of the bare ones. They have not become blistered or rusted when they are exposed in tap-water for at least 3 months. It is indicated that the polyaniline microlatex is a sort of environmental friend coating.
2005, 20(2): 33-36,44.
DOI: 10.19515/j.cnki.1003-1545.2005.02.009
Abstract：
The status and prospects of high Tc superconducting material in marine application involving superconducting cable and motor, superconducting mine sweeper, electromagnetic launcher, energe storage system etc.
The status and prospects of high Tc superconducting material in marine application involving superconducting cable and motor, superconducting mine sweeper, electromagnetic launcher, energe storage system etc.
2005, 20(2): 37-41.
DOI: 10.19515/j.cnki.1003-1545.2005.02.010
Abstract：
In this review, the recent achievements in the synthesis of TiO2 nanomaterials (particles, tubes, wires, thin films, film electrolyte and porous fibers) as well as their applications in photo-catalysis are presented. The advantages and shortcomings of each synthesis techniques covering microemulsions, templating, sol-gel, VCD and LCD methods are compared with each other. Finally, the further research work is suggested.
In this review, the recent achievements in the synthesis of TiO2 nanomaterials (particles, tubes, wires, thin films, film electrolyte and porous fibers) as well as their applications in photo-catalysis are presented. The advantages and shortcomings of each synthesis techniques covering microemulsions, templating, sol-gel, VCD and LCD methods are compared with each other. Finally, the further research work is suggested.
2005, 20(2): 42-44.
DOI: 10.19515/j.cnki.1003-1545.2005.02.011
Abstract：
The working life of the pump parts such as impeller shortened when sea water was used to substitute fresh water in inshore power plant dust disposing system. To solve this problem, an anti-corrosion steel was employed to substitute the original material of the parts. It is proved in practice that the working life is elongated and the operation of the dust disposing system is guaranteed with the new pump parts.
The working life of the pump parts such as impeller shortened when sea water was used to substitute fresh water in inshore power plant dust disposing system. To solve this problem, an anti-corrosion steel was employed to substitute the original material of the parts. It is proved in practice that the working life is elongated and the operation of the dust disposing system is guaranteed with the new pump parts.
