Composition and Structure of Ti-6Al-4V Alloy Plasma-based Ion Implanted with Nitrogen

The composition and structure of Ti 6Al 4V alloy plasma based ion implanted with nitrogen was investigated.The nitrogen depth distribution shows more antiballistic with distribution peak heightened with increased implantation time(dose),and more like a parabola at the low implantation pulse voltage.When implantation pulse voltage is increased,the implantation depth increased with the nitrogen distribution peak being deepened,widened and lowered somewhat.TiN,TiN+Ti 2N,or Ti 2N second phases were formed in the implanted layer.The relative percentage of nitrogen content in the form of TiN increases when going deeper into the implanted(TiN formed) layer.The increase of implantation pulse width and/or time is favourable for the formation of TiN rather than Ti 2N.It is unfavourable for formation of any nitrides when implantation pulse voltage is decreased to 30kV or less.Tiny crystalline particles (made mainly of Ti 2N and a smaller percentage of TiO 2 phases) of regular shapes such as triangle and tetragon, etc .(about 20 nm) are found distrbuted dispersively in the near surface region of samples implanted at the high implantation pulse voltage (75kV).

Deposition of DLC Coating on Biomedical TiNi Alloys by Plasma Based Ion Implantation to Improve Surface Properties

Diamond-like carbon （DLC） films were successfully deposited on Ti- 50.8 at% Ni using plasma based ion implantation （PBII） technique. The influence of the pulsed negative bias voltage applied to the substrate from 12 kV to 40 kV on the microstracture, nano-indentation hardness and Young＇ s modulus, the surface characteristics and corrosion resistant property as well as hemocompatibility were investigated. The experimental resalts showed that C 1 s peak depended heavily on the bias voltage. With the increase of bias voltage, the ratio of sp2 / sp3 first decreased, reaching a minimum value at 20 kV, and then increased. The DLC coating deposited at 20 kV showed the highest hardness and elastic modulus values as a result of lower sp2/sp3 ratio. The RMS values first decreased from 7.202nm（12 kV） to 5.279 nm（20 kV）, and then increased to 11.449 nm（30 kV） and 7.060 nm（ 40 kV）. The uncoated TiNi alloy showed severe pitting corrosion, due to the presence of Cl-ions in the solution. On the contrary, the DLC coated sample showed very little pitting corrosion and behaved better corrosion resistant property especially for the specimens deposited at 20 kV bias voltages. The platelet adhesion test show that the hemocompatibility of DLC coated TiNi alloy is much better than that of bare TiNi alloy, and the hemocompatibility performance of DLC coated TiNi alloy deposited at 20 kV is superior to that of other coated specimens.

Performance of a New Ion Source for KSTAR Tokamak Plasma Heating

In the experimental campaign of 2010 and 2011 on KSTAR, the NBI-1 system was equipped with one prototype ion source and operated successfully, providing a neutral beam power of 0.7-1.6 MW to the tokamak plasma. The new ion source planned for the 2012 KSTAR campaign had a much more advanced performance compared with the previous one. The target performance of the new ion source was to provide a neutral deuterium beam of 2 MW to the tokamak plasma. The ion source was newly designed, fabricated, and assembled in 2011. The new ion source was then conditioned up to 64 A/100 keV over a 2-hour beam extraction and performance tested at the NB test stand （NBTS） at the Korea Atomic Energy Research Institute （KAERI） in 2012. The measured optimum perveance at which the beam divergence is a minimum was about 2.5μP, and the minimum beam divergent angle was under 1.0° at 60 keV. These results indicate that the 2.0 MW neutral beam power at 100 keV required for the heating of plasma in KSTAR can be delivered by the installation of the new ion source in the KSTAR NBI-1 system.

Characteristics of Cu implantation into Si by PBII using UBMS cathode

The implantation of Cu into Si substrate was carried out by plasma based ion implantation (PBII) using unbalanced magnetron sputtering (UBMS) cathode as the metal plasma source. The different pulse bias ( U p) and the distance between the cathode and the samples ( d s-t ) were chosen to research the characteristics of this method. The results show that the implantation of metal ions can be realized by the metal plasma source of UBMS cathode. The physical process such as the metal ion pure implantation, the gas ion implantation, the recoil implantation of the metal atoms, the deposition of the metal particles and the re sputtering of the metal film depend on the energy, dose and deposition rate of the ions (Cu +, Ar +). The metal plasma based ion implantation of Cu into Si substrate is favored by selecting higher U p (60 kV) and larger d s-t (200 mm). [

Extraction and separation of Nd(Ⅲ), Sm(Ⅲ), Dy(Ⅲ), Fe(Ⅲ), Ni(Ⅱ), and Cs(Ⅰ) from concentrated chloride solutions with N,N,N',N'-tetra(2-ethylhexyl) diglycolamide as new extractant

The feasibility of using N,N,N＇,N＇-tetra（2-ethylhexyl）diglycolamide （TEHDGA） in 75 vol.% n-dodecane-25 vol.% n-octanol as agents for the extraction and separation ofNd（III）, Sm（III）, Dy（llI）, Fe（III）, Ni（II）, and Cs（I） from concentrated chlo- ride solution was investigated. Different extraction behaviors were obtained towards rare earth elements （REE） studied and Fe（IIl）, Ni（II） and Cs（I）. Efficient separation of Nd（III）, Sm（III） and Dy（III） from Fe（III）, Ni（II）, and Cs（I） was achieved by TEHDGA, depending on the HCI, HNO3 or H2SO4 concentration. A systematic investigation was carried out on the detailed extraction prop- erties of Nd（III）, Sm（III）, and Dy（III） with TEHDGA from chloride media. The IR spectra of the extracted species were investi- gated.