A series of positive electrodes for Ni/MH battery were fabricated by addition of CoO.The morphology and microstructure of the electrodes were examined by SEM and EDS, and electrochemical behavior was investigated in t...A series of positive electrodes for Ni/MH battery were fabricated by addition of CoO.The morphology and microstructure of the electrodes were examined by SEM and EDS, and electrochemical behavior was investigated in three-compartment appliances at room temperature.The electrochemical performance of the positive electrodes with CoO was improved. Under the same charge-discharge cycle, the electrodes with CoO showed higher specific capacity, lower charge mean voltage and higher discharge mean voltage. But ...展开更多
NiCrAlY+(ZrO_2+Y_2O_3)thermal barrier coating was prepared on the surface of refractory steel 1Cr18Ni9Ti with plasma spraying technique. The phases and microstructure of the thermal barrier coating were determined by ...NiCrAlY+(ZrO_2+Y_2O_3)thermal barrier coating was prepared on the surface of refractory steel 1Cr18Ni9Ti with plasma spraying technique. The phases and microstructure of the thermal barrier coating were determined by scanning electron microscopy(SEM) and X-ray diffraction(XRD). The results show that the bonding between thermal barrier coating and substrate is sound. The surface hardness of 1Cr18Ni9Ti reaches up to 1000 HV, but that of substrate is only 300HV. The patterns sprayed with CoNiCrAlY+(ZrO_2+Y_2O_3) ceramic coating have a good heat insulation effect at 800℃ for heat insulation temperature difference reaches 54℃, which increases the operating temperature and service life of refractory steel.展开更多
The corrosion resistance of NiCrAl+(ZrO2+Y2O3)thermal barrier coating, formed with the plasma spraying technique, on the 18[CD*2]8 steel surface was investigated. The phase structure and morphology of the coating we...The corrosion resistance of NiCrAl+(ZrO2+Y2O3)thermal barrier coating, formed with the plasma spraying technique, on the 18[CD*2]8 steel surface was investigated. The phase structure and morphology of the coating were analyzed by means of X-ray diffraction(XRD) and scanning electron microscopy(SEM). The electrochemical corrosion behavior of the coating in 1.0mol/L H2SO4 solution was studied by using electrochemical measurement methods. The results show that the gradient plasma spraying coating is composed of the NiCrAlY primer coating and the (ZrO2+Y2O3 ) top coating, and the coating thickness is 360μm. The microhardness of coating reaches 1100HV. The corrosion resistance of the plasma sprayed coating of the 18[CD*2]8 steel surface is about 5 times as great as that of the original pattern. The corrosion resistance of the coating is enhanced notably.展开更多
Corrosive failure is frequently found in petrochemical pipelines which may lead to the leakage of the pipes and even the shutdown of the system. However, the corrosion mechanism is still not well understood due to the...Corrosive failure is frequently found in petrochemical pipelines which may lead to the leakage of the pipes and even the shutdown of the system. However, the corrosion mechanism is still not well understood due to the complex service environment, e.g. the corrosive fluids and the long term operation at higher temperature. The corrosion behaviour of a petrochemical pipe elbow was evaluated via visual examination and microanalysis with optical microscope and scanning electron microscope(SEM) together with energy dispersive analysis X-ray(EDAX). The corresponding corrosion mechanisms, the combination of grain boundary attach and the crevice attach together with the flow-accelerated corrosion, were proposed consequently.展开更多
Recently, minimally invasive surgeries using guide-wire, catheter, stent etc. have spread rapidly as the diagnosis and the medical treatment for a cancer, a disease in a circulatory organ etc. Currently, further maneu...Recently, minimally invasive surgeries using guide-wire, catheter, stent etc. have spread rapidly as the diagnosis and the medical treatment for a cancer, a disease in a circulatory organ etc. Currently, further maneuverability and functionability of those devices are strongly desired in order to be used widely and safely. Although Ti-Ni shape memory alloys have been used in medical devices such orthodontic wire, guide-wire, it has been suspected that Ni is allergenic and carcinogenic to the human body. Thus the development of Ni-free shape memory alloys has been strongly required. Recently, several Ni-free beta-titanium alloys such as Ti-Mo-Al, Ti-Mo-Ga, Ti-Nb-Al have been developed as new-type shape memory alloys. We have been studying Ti-Mo based beta-titanium alloys and Ti-Mo-Sn alloy has constantly super elasticity of 3%.The purpose of present study is to propose the micro catheter with thin wall and high flexibility using To-Mo-Sn alloys tube on the basis of its mechanical properties.展开更多
基金supported by the National High Technology Development Program of China (No. 2003AA302420)the National Major Basic Research Project (No. GT20000264-06) of MOST, China
文摘A series of positive electrodes for Ni/MH battery were fabricated by addition of CoO.The morphology and microstructure of the electrodes were examined by SEM and EDS, and electrochemical behavior was investigated in three-compartment appliances at room temperature.The electrochemical performance of the positive electrodes with CoO was improved. Under the same charge-discharge cycle, the electrodes with CoO showed higher specific capacity, lower charge mean voltage and higher discharge mean voltage. But ...
文摘NiCrAlY+(ZrO_2+Y_2O_3)thermal barrier coating was prepared on the surface of refractory steel 1Cr18Ni9Ti with plasma spraying technique. The phases and microstructure of the thermal barrier coating were determined by scanning electron microscopy(SEM) and X-ray diffraction(XRD). The results show that the bonding between thermal barrier coating and substrate is sound. The surface hardness of 1Cr18Ni9Ti reaches up to 1000 HV, but that of substrate is only 300HV. The patterns sprayed with CoNiCrAlY+(ZrO_2+Y_2O_3) ceramic coating have a good heat insulation effect at 800℃ for heat insulation temperature difference reaches 54℃, which increases the operating temperature and service life of refractory steel.
文摘The corrosion resistance of NiCrAl+(ZrO2+Y2O3)thermal barrier coating, formed with the plasma spraying technique, on the 18[CD*2]8 steel surface was investigated. The phase structure and morphology of the coating were analyzed by means of X-ray diffraction(XRD) and scanning electron microscopy(SEM). The electrochemical corrosion behavior of the coating in 1.0mol/L H2SO4 solution was studied by using electrochemical measurement methods. The results show that the gradient plasma spraying coating is composed of the NiCrAlY primer coating and the (ZrO2+Y2O3 ) top coating, and the coating thickness is 360μm. The microhardness of coating reaches 1100HV. The corrosion resistance of the plasma sprayed coating of the 18[CD*2]8 steel surface is about 5 times as great as that of the original pattern. The corrosion resistance of the coating is enhanced notably.
文摘Corrosive failure is frequently found in petrochemical pipelines which may lead to the leakage of the pipes and even the shutdown of the system. However, the corrosion mechanism is still not well understood due to the complex service environment, e.g. the corrosive fluids and the long term operation at higher temperature. The corrosion behaviour of a petrochemical pipe elbow was evaluated via visual examination and microanalysis with optical microscope and scanning electron microscope(SEM) together with energy dispersive analysis X-ray(EDAX). The corresponding corrosion mechanisms, the combination of grain boundary attach and the crevice attach together with the flow-accelerated corrosion, were proposed consequently.
文摘Recently, minimally invasive surgeries using guide-wire, catheter, stent etc. have spread rapidly as the diagnosis and the medical treatment for a cancer, a disease in a circulatory organ etc. Currently, further maneuverability and functionability of those devices are strongly desired in order to be used widely and safely. Although Ti-Ni shape memory alloys have been used in medical devices such orthodontic wire, guide-wire, it has been suspected that Ni is allergenic and carcinogenic to the human body. Thus the development of Ni-free shape memory alloys has been strongly required. Recently, several Ni-free beta-titanium alloys such as Ti-Mo-Al, Ti-Mo-Ga, Ti-Nb-Al have been developed as new-type shape memory alloys. We have been studying Ti-Mo based beta-titanium alloys and Ti-Mo-Sn alloy has constantly super elasticity of 3%.The purpose of present study is to propose the micro catheter with thin wall and high flexibility using To-Mo-Sn alloys tube on the basis of its mechanical properties.