Vacuum arc ion sources are known for delivering high currents of ion beams in many technological applications. There is a great need in the present ion accelerator injection research for a titanium vacuum arc source t...Vacuum arc ion sources are known for delivering high currents of ion beams in many technological applications. There is a great need in the present ion accelerator injection research for a titanium vacuum arc source to produce high-ionized plasma, in which its parameter is extremely important to match the extractors geometry and the extraction voltage. In this paper, the radial and angular distributions of the titanium cathodic vacuum arc plasma parameters are measured by a cylindrical Langmuir probe and analyzed by the Druyvesteyn method from the I-V curves. The electron density ne is about 10^（17）m^（-3） and the effective electron temperature Tefr is in the range of 6.12-11.11 eV in the free expansion cup before the ion extraction. The measured distribution of ne over the expansion cross-section is non-uniform and axially unsymmetrical with its form similar to the Gaussian distribution, and most of the plasma is concentrated into an area whose radius is smaller than 5 mm. Teff has a nearly uniform distribution over the expansion cross-section during the discharge. The results of the plasma parameters＇ non-uniformity encourage the researchers to make some optimization designs to improve the parameter distributions, and then to facilitate ion extraction.展开更多
The thermionic vacuum arc （TVA） is a new type of plasma source, which generates a pure metal and ceramic vapour plasma containing ions with a directed energy. TVA discharges can be ignited in high vacuum conditions ...The thermionic vacuum arc （TVA） is a new type of plasma source, which generates a pure metal and ceramic vapour plasma containing ions with a directed energy. TVA discharges can be ignited in high vacuum conditions between a heated cathode （electron gun） and an anode （tungsten crucible） containing the material. The accelerated electron beam, incident on the anode, heats the crucible, together with its contents, to a high temperature. After establishing a steadystate density of the evaporating anode material atoms, and when the voltage applied is high enough, a bright discharge is ignited between the electrodes. We generated silver and Al2O3 TVA discharges in order to compare the metal and ceramic TVA discharges. The electrical and optical characteristics of silver and Al2O3 TVA discharges were analysed. The TVA is also a new technique for the deposition of thin films. The film condenses on the sample from the plasma state of the vapour phase of the anode material, generated by a TVA. We deposited silver and Al2O3 thin films onto an aluminium substrate layer-by-layer using their TVA discharges, and produced micro and/or nano-layer Ag-Al2O3 composite samples. The composite samples using scanning electron microscopy was also analysed.展开更多
In this work, the deposition process features of a copper coating on stainless steel substrate, using the pulse vacuum arc spraying method were researched. A continuous layer of copper was deposited on a stainless ste...In this work, the deposition process features of a copper coating on stainless steel substrate, using the pulse vacuum arc spraying method were researched. A continuous layer of copper was deposited on a stainless steel substrate, and a high degree of coating adhesion to the substrate was demonstrated. The thickness of coating using application time was calculated, and the surface unevenness was estimated. Inside the coating layer substrate material elements were observed, that could appear as a result of simultaneously plasma spraying on the surface of the substrate. The feature of this method was discovered, that surface plasma plays a significant role in the deposition process. Finally, it was shown that the device with a pulsed arc could effectively be used in industry, since it is possible to change the layer thickness in the range of hundreds of microns by varying the deposition time.展开更多
Detailed design of the vacuum feedthrough for the ion cyclotron radio frequency （ICRF） antenna in EAST, along with an electro-analysis and thermal structural analysis, is pre- sented. The electric field, the voltage...Detailed design of the vacuum feedthrough for the ion cyclotron radio frequency （ICRF） antenna in EAST, along with an electro-analysis and thermal structural analysis, is pre- sented. The electric field, the voltage standing wave ratio （VSWR） and the stresses in the vacuum feedthrough are studied. A method using the rings of oxygen-free copper as the cushion and macro- beam plasma arc welding is applied in the assembly to protect the ceramic from being damaged during welding. The vacuum leak test on the prototype of vacuum feedthrough is introduced.展开更多
A major obstacle to the broad application of cathodic arc plasma deposition is the presence of macroparticles. In this paper, the properties of the large rectangular arc ion plating with a magnetic filtering shutter s...A major obstacle to the broad application of cathodic arc plasma deposition is the presence of macroparticles. In this paper, the properties of the large rectangular arc ion plating with a magnetic filtering shutter system to filter macroparticles are studied. It is proposed that the macroparticles in the plasma beam are effectively removed with the magnetic filtering shutter system, and the quality of the deposited films is improved.展开更多
文摘Vacuum arc ion sources are known for delivering high currents of ion beams in many technological applications. There is a great need in the present ion accelerator injection research for a titanium vacuum arc source to produce high-ionized plasma, in which its parameter is extremely important to match the extractors geometry and the extraction voltage. In this paper, the radial and angular distributions of the titanium cathodic vacuum arc plasma parameters are measured by a cylindrical Langmuir probe and analyzed by the Druyvesteyn method from the I-V curves. The electron density ne is about 10^（17）m^（-3） and the effective electron temperature Tefr is in the range of 6.12-11.11 eV in the free expansion cup before the ion extraction. The measured distribution of ne over the expansion cross-section is non-uniform and axially unsymmetrical with its form similar to the Gaussian distribution, and most of the plasma is concentrated into an area whose radius is smaller than 5 mm. Teff has a nearly uniform distribution over the expansion cross-section during the discharge. The results of the plasma parameters＇ non-uniformity encourage the researchers to make some optimization designs to improve the parameter distributions, and then to facilitate ion extraction.
基金supported by the Eskisehir Osmangazi University project(200319009)
文摘The thermionic vacuum arc （TVA） is a new type of plasma source, which generates a pure metal and ceramic vapour plasma containing ions with a directed energy. TVA discharges can be ignited in high vacuum conditions between a heated cathode （electron gun） and an anode （tungsten crucible） containing the material. The accelerated electron beam, incident on the anode, heats the crucible, together with its contents, to a high temperature. After establishing a steadystate density of the evaporating anode material atoms, and when the voltage applied is high enough, a bright discharge is ignited between the electrodes. We generated silver and Al2O3 TVA discharges in order to compare the metal and ceramic TVA discharges. The electrical and optical characteristics of silver and Al2O3 TVA discharges were analysed. The TVA is also a new technique for the deposition of thin films. The film condenses on the sample from the plasma state of the vapour phase of the anode material, generated by a TVA. We deposited silver and Al2O3 thin films onto an aluminium substrate layer-by-layer using their TVA discharges, and produced micro and/or nano-layer Ag-Al2O3 composite samples. The composite samples using scanning electron microscopy was also analysed.
文摘In this work, the deposition process features of a copper coating on stainless steel substrate, using the pulse vacuum arc spraying method were researched. A continuous layer of copper was deposited on a stainless steel substrate, and a high degree of coating adhesion to the substrate was demonstrated. The thickness of coating using application time was calculated, and the surface unevenness was estimated. Inside the coating layer substrate material elements were observed, that could appear as a result of simultaneously plasma spraying on the surface of the substrate. The feature of this method was discovered, that surface plasma plays a significant role in the deposition process. Finally, it was shown that the device with a pulsed arc could effectively be used in industry, since it is possible to change the layer thickness in the range of hundreds of microns by varying the deposition time.
文摘Detailed design of the vacuum feedthrough for the ion cyclotron radio frequency （ICRF） antenna in EAST, along with an electro-analysis and thermal structural analysis, is pre- sented. The electric field, the voltage standing wave ratio （VSWR） and the stresses in the vacuum feedthrough are studied. A method using the rings of oxygen-free copper as the cushion and macro- beam plasma arc welding is applied in the assembly to protect the ceramic from being damaged during welding. The vacuum leak test on the prototype of vacuum feedthrough is introduced.
文摘A major obstacle to the broad application of cathodic arc plasma deposition is the presence of macroparticles. In this paper, the properties of the large rectangular arc ion plating with a magnetic filtering shutter system to filter macroparticles are studied. It is proposed that the macroparticles in the plasma beam are effectively removed with the magnetic filtering shutter system, and the quality of the deposited films is improved.
