The paper is dedicated to the lifetime prolongation of the tools designed for deep-hole drilling. Among available methods, an ion implantation process was used to improve the durability of tungsten ...carbide (WC)-Co guide pads. Nitrogen fluencies of 3 × 10
cm
, 4 × 10
cm
and 5 × 10
cm
were applied, and scanning electron microscope (SEM) observations, energy dispersive spectroscopy (EDS) analyses, X-ray photoelectron spectroscopy (XPS) and Secondary Ion Mass Spectrometry (SIMS) measurements were performed for both nonimplanted and implanted tools. The durability tests of nonimplanted and the modified tools were performed in industrial conditions. The durability of implanted guide pads was above 2.5 times more than nonimplanted ones in the best case, presumably due to the presence of a carbon-rich layer and extremely hard tungsten nitrides. The achieved effect may be attributed to the dissociation of tungsten carbide phase and to the lubrication effect. The latter was due to the presence of pure carbon layer with a thickness of a few dozen nanometers. Notably, this layer was formed at a temperature of 200 °C, much smaller than in previously reported research, which makes the findings even more valuable from economic and environmental perspectives.
The paper presents the effect of nitrogen ion implantation on the tool life of the tools commonly used in the furniture industry for drilling particleboards. Nitrogen ions with different accelerating ...voltages of 25, 40, 55, and 70 kV and a fluence of 5 × 10
cm
were implanted into the surface of commercially available high-speed steel (HSS) drills, using the implanters without mass-separated ion beams. The tests were carried out in a computerized numerical control (CNC) machining center used in the furniture industry. Based on the measurements of the direct tool wear indicator (W), the drill wear curves were determined and the relative tool life index, standard deviation, coefficient of variation, and the implantation quality index of tool life were calculated. The studies have shown that the modification of the drill surface layer by the nitrogen ion implantation process increases the tool life. The obtained results allow the research to be the continued in a wider scope.
Rare earth-doped zinc oxide (ZnO:RE) systems are attractive for future optoelectronic devices such as phosphors, displays, and LEDs with emission in the visible spectral range, working even in a ...radiation-intense environment. The technology of these systems is currently under development, opening up new fields of application due to the low-cost production. Ion implantation is a very promising technique to incorporate rare-earth dopants into ZnO. However, the ballistic nature of this process makes the use of annealing essential. The selection of implantation parameters, as well as post-implantation annealing, turns out to be non-trivial because they determine the luminous efficiency of the ZnO:RE system. This paper presents a comprehensive study of the optimal implantation and annealing conditions, ensuring the most efficient luminescence of RE3+ ions in the ZnO matrix. Deep and shallow implantations, implantations performed at high and room temperature with various fluencies, as well as a range of post-RT implantation annealing processes are tested: rapid thermal annealing (minute duration) under different temperatures, times, and atmospheres (O2, N2, and Ar), flash lamp annealing (millisecond duration) and pulse plasma annealing (microsecond duration). It is shown that the highest luminescence efficiency of RE3+ is obtained for the shallow implantation at RT with the optimal fluence of 1.0 × 1015 RE ions/cm2 followed by a 10 min annealing in oxygen at 800 °C, and the light emission from such a ZnO:RE system is so bright that can be observed with the naked eye.
The paper presents the effect of nitrogen ion implantation on tool wear and tool life during the sawing of wood-based materials in the industrial production of door frames. The circular saw blades ...used in machining had WC-Co carbide teeth. Saw teeth were modified by ion implantation. The total implanted dose of nitrogen ions was 5 × 1017 cm−2 (2 × 2.5 × 1017 cm−2) and ions were implanted at 50 kV acceleration voltage. Tool wear testing was carried out under industrial production conditions for the door frames made of wood-based materials. The wear of circular saw teeth was evaluated under an optical microscope. Based on the tool’s wear and machining distance, a mathematical linear model of the non-treated and ion-implanted tools’ life was developed using the linear least squares method. The study showed less wear of the implanted circular saw blades and a significant increase in the estimated lifetime of modified tools compared to non-treated (control) tools. At the same time, activation of the surface of the implanted circular saw teeth was observed, manifested by an increase in adhesion and the appearance of the secondary structures on the WC-Co surface.
Under construction for the stellarator project Wendestein 7-X is a neutral beam heating system based on RF driven positive ion sources. It is planned to start operation with 2 sources capable of ...injecting 5 MW of heating power in deuterium. This paper gives the current status and future plans of the construction of the injector boxes and subsequent installation in the experimental hall. The fruitful collaboration with the National Center for Nuclear Research in Swierk, Poland is also detailed. Lastly, results from an initial study on fast ions in Wendelstein 7-X will be given.
Rare earth-doped zinc oxide (ZnO:RE) systems are attractive for future optoelectronic devices such as phosphors, displays, and LEDs with emission in the visible spectral range, working even in a ...radiation-intense environment. The technology of these systems is currently under development, opening up new fields of application due to the low-cost production. Ion implantation is a very promising technique to incorporate rare-earth dopants into ZnO. However, the ballistic nature of this process makes the use of annealing essential. The selection of implantation parameters, as well as post-implantation annealing, turns out to be non-trivial because they determine the luminous efficiency of the ZnO:RE system. This paper presents a comprehensive study of the optimal implantation and annealing conditions, ensuring the most efficient luminescence of REsup.3+ ions in the ZnO matrix. Deep and shallow implantations, implantations performed at high and room temperature with various fluencies, as well as a range of post-RT implantation annealing processes are tested: rapid thermal annealing (minute duration) under different temperatures, times, and atmospheres (Osub.2, Nsub.2, and Ar), flash lamp annealing (millisecond duration) and pulse plasma annealing (microsecond duration). It is shown that the highest luminescence efficiency of REsup.3+ is obtained for the shallow implantation at RT with the optimal fluence of 1.0 × 10sup.15 RE ions/cmsup.2 followed by a 10 min annealing in oxygen at 800 °C, and the light emission from such a ZnO:RE system is so bright that can be observed with the naked eye.
Rare earth-doped zinc oxide (ZnO:RE) systems are attractive for future optoelectronic devices such as phosphors, displays, and LEDs with emission in the visible spectral range, working even in a ...radiation-intense environment. The technology of these systems is currently under development, opening up new fields of application due to the low-cost production. Ion implantation is a very promising technique to incorporate rare-earth dopants into ZnO. However, the ballistic nature of this process makes the use of annealing essential. The selection of implantation parameters, as well as post-implantation annealing, turns out to be non-trivial because they determine the luminous efficiency of the ZnO:RE system. This paper presents a comprehensive study of the optimal implantation and annealing conditions, ensuring the most efficient luminescence of RE
ions in the ZnO matrix. Deep and shallow implantations, implantations performed at high and room temperature with various fluencies, as well as a range of post-RT implantation annealing processes are tested: rapid thermal annealing (minute duration) under different temperatures, times, and atmospheres (O
, N
, and Ar), flash lamp annealing (millisecond duration) and pulse plasma annealing (microsecond duration). It is shown that the highest luminescence efficiency of RE
is obtained for the shallow implantation at RT with the optimal fluence of 1.0 × 10
RE ions/cm
followed by a 10 min annealing in oxygen at 800 °C, and the light emission from such a ZnO:RE system is so bright that can be observed with the naked eye.
The paper presents the preliminary results of cellulose modification by ion implantation. Three types of ions were implanted, i.e., copper, zinc and silver with fluences of 5 × 1014 and 5 × 1015 ...cm−2, respectively. The acceleration voltage of the implanted ions was 30 kV. The ion penetration depth profiles showed differences, especially in the Cu and Ag cases, due to the different ion beams of these elements. The implantation of cellulose with ions clearly changed the wettability of the material surface in the direction of hydrophobicity. The impact of implantation on the growth of the cellulose surface by mold fungi was also noticeable. Only the silver ion implantation had a negative effect on the growth of the Trichoderma viride fungus but did not cause a complete inhibition of growth. Cellulose implantation with Cu and Zn ions clearly stimulated the growth of fungi on the surface of the polymer.
This work explores an effect of nitrogen ion implantation on the life time of WC-Co tools used in particleboard milling. Nitrogen ions with different energy of 5, 50, and 500 keV and fluence of 1e17 ...and 5e17 cm
−2
were implanted into the surface of commercially available WC-Co composite indexable knives, using the implanters with mass-separated ion beams. Both untreated and modified samples were subjected to microstructural and durability tests. Microstructural tests involved surface observation, determination of the nature of wear and cracks, determination of element depth profiles, and phase changes occurring in the modified area. Durability tests were conducted with the use of a computerized numerical control (CNC) machining center. The tests included determination of wear curves and calculation of quantities such as cutting length, relative tool life index, standard deviation, standard error, coefficient of variation and quality index and wear increases. Additionally, a histogram of the relative durability distribution of samples implanted with N
+
was determined. In this study, an attempt was made to relate the durability results with the microstructure of the knives. Tools modified with a nitrogen ion beam of 50 keV showed the best durability results.
Monocrystalline ZnO samples were implanted with Co (transition metal) and with Ar and Kr noble gas ions, with energies and doses leading to comparable damage in the host lattice as regards its ...extension and magnitude. Structural properties of the implanted ZnO were investigated by channeled Rutherford Backscattering Spectrometry (cRBS), aided with calculations using McChasy code. It was shown that the damage produced by implantation does not reach an amorphization level in all cases and is produced deeper in the crystal in comparison with theoretical predictions. The range and magnitude of damaged region are comparable in all cases of ion implantation.
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