bluuebunny/crossref_metadata_2025_split huggingface dataset:
Work function of the caesiated converter surface at the BATMAN Upgrade H− ion source at different operational scenarios
Authors: Heiler A , Wimmer C , Berner J , Fantz U 
Published: May 2024

Abstract
Since negative hydrogen ion sources for neutral beam injection (NBI) systems rely on the surface production of negative hydrogen ions, Cs is injected to lower the work function of the extraction electrode surface. The adsorbed Cs layers are affected by residual gases from the given non-UHV conditions as well as by reactive hydrogen species during plasma phases, which leads to a complex surface chemistry and the occurrence of temporal changes of the work function. To control the work function and get insight into its temporal dynamics, an absolute work function diagnostic has been developed for ion sources with which measurements can be performed in vacuum phases between pulses. The diagnostic is applied at the BATMAN Upgrade test facility, which is equipped with the prototype RF ion source for the ITER NBI. It is shown that the Cs conditioning of the ion source leads to a dramatic decrease in the work function to ultra-low values < 1.5 eV. First measurements after the application of 1000 s pulses indicate that the ultra-low work function layer is not stable upon long-term plasma exposure and it is revealed that high dynamics of the Cs surface properties are given right after the pulse.
Towards ITER-Relevant CW Extraction at Negative Ion Sources for Fusion
Authors: Wünderlich D. , Wimmer C. , den Harder N. , Barnes M. , Fröschle M. , Heiler A. , Navarro A. , Riedl R. , Yordanov D. , Fantz U. , Heinemann B. ,   NNBI Team
Published: May 2024

Abstract
Negative hydrogen or deuterium ion sources for neutral beam injection (NBI) systems used at fusion devices are based on the surface production process at a caesiated low work function converter surface. While producing a stable and globally homogeneous negative ion beam is not an issue, during long pulses typically a pronounced increase in the co-extracted electrons is observed, limiting the pulse length or the achievable performance. This effect is particularly pronounced in deuterium and it is attributed to an increasing work function of the converter surface. In the last years the negative ion source test facilities at IPP Garching, BATMAN Upgrade (using the small prototype source) and ELISE (using a source of the same width but only half the height of the ITER NBI source) have been converted into CW machines, making possible investigating at ITER conditions counter-measures for the increase in the co-extracted electrons. Investigations are performed, mainly at ELISE, on homogenizing and stabilizing the co-extracted electrons by affecting the ion source plasma close to the converter surface by means of biasing (additional) surfaces in the plasma.
High current positive ion source for Copernicus NBI based on a cold-cathode arc plasma generator
Authors: Shimabukuro Y , Franzen K , Korepanov S 
Published: May 2024

Abstract
The NBI system based on positive ions to be applied for TAE’s next-generation field reversed configuration experiment, Copernicus, has been designed. The beamlines are longer in the new system, so the required beam divergence smaller relative to the NBI system on TAE’s current device. This requirement motivates a change from slot-shaped apertures to circular in the plasma grid. The influence of changing the aperture shape on the divergence and total beam current across the extraction area has been examined. When considering spatial uniformity in calculations, it is expected that a beam current value of 173 A and a beam divergence angle of 17 mrad will be achieved, exceeding the required values by 15%. An octagonal-shaped ion source has also been developed for a future upgrade targeting 2.5 s long pulse operation, and the estimation indicates 83% source plasma uniformity with concurrent suppression of thermal loads. The development of multiple plasma diagnostics for assessing uniformity and proton ratios has been completed to validate these estimations and optimize the ion source dimensions.
Factors Influencing the Fluctuation Amplitude of the H− Ion Beam Extracted from an RF Wave Excited Ion Source Plasma
Authors: Wada Motoi , Shibata Takanori , Shinto Katsuhiro 
Published: May 2024

Abstract
The beam oscillation of J-PARC ion source is being studied as AC electric field at 2 MHz ion source driving frequency can directly change the extraction characteristics of both H− ions and electrons. The internal RF antenna inducing the electric field generated two peaks of plasma production during one RF cycle as confirmed by 4 MHz modulation of Balmer-alpha (Hα) emission intensity. The coupling between the plasma production at 4 MHz and the oscillation of the local plasma potential in the vicinity of the extraction hole at 2 MHz can cause 6 MHz oscillation, which was observed in the measurement of extraction current from the ion source. Phase-delay of Hα intensities from the source plasma and those of the extraction electron current were compared with the RF input signal to the amplifier.
Modelling of plasma discharge in a filament negative ion source
Authors: Candeloro V , Sartori E , Kisaki M , Kashiwagi M , Tobari H , Serianni G 
Published: May 2024

Abstract
Most of the currently operating Negative ion Neutral Beam Injectors (N-NBIs) exploit filament powered sources for the generation of beam ions. Being widely used in fusion experiments, the filament arc technology has been thoroughly investigated and optimized over the years, allowing to achieve excellent performances in terms of extracted beam optics. The source geometry, the magnetic field topology and the arc power strongly influence both the plasma discharge and the background gas properties and, consequently, the beam features. In this framework, this contribution describes a numerical investigation of the plasma properties in a filament-powered negative ion source, performed by means of a 2D3V Particle In Cell-Monte Carlo Collisions (PIC-MCC) code. Specifically, we discuss plasma formation by the thermionic electrons emitted by the filaments, investigating their interaction with the background gas. We also study the plasma diffusion through the magnetic filter field and how the latter modifies plasma density, electron temperature and plasma potential along the axial direction when approaching the plasma facing electrode.
Status of the High-Current Electron-Beam Ion Source Charge Breeder for the Facility for Rare-Isotope Beams
Authors: Son Hyock-Jun , Lapierre Alain , Schwarz Stefan , Villari Antonio C.C. 
Published: May 2024

Abstract
The Reaccelerator (ReA) of the Facility for Rare-Isotope Beams (FRIB) employs an Electron-Beam Ion Trap (EBIT) as a charge breeder to reaccelerate rare-isotope beams up to 12 MeV/u. The ReA EBIT produces an electron current of 300 – 600 mA. The maximum trap capacity of the ReA EBIT is 1010 elementary charges. FRIB production rates are expected to exceed 1010 particles/s in some cases in the future. There is also a user demand for reaccelerated stable-isotope beams of more than 1010 pps. To handle these rates and provide redundancy, a High Current Electron-Beam Ion Source (HCEBIS) has been built and is now being commissioned. An electron-beam current of 2 A with a 50 % duty cycle has been transported through a 4-T field. An upcoming upgrade to increase the electron-beam current up to 4 A will allow for a maximum trap capacity of 2.4×1011 elementary charges. We present the status of the HCEBIS, including the results of the electron-beam commissioning and systematic studies.
Upgrade and Improvement of the TRIUMF ECRIS Charge State Booster
Authors: Adegun J , Ames F , Kester O 
Published: May 2024

Abstract
Recently, the RF system of the TRIUMF electron cyclotron resonance ion source charge state booster (ECRIS CSB) underwent an upgrade to implement two-frequency heating using a single waveguide. The injection and extraction optics, as well as the injection and extraction systems, were carefully modelled and systematically optimized to improve the efficiency and beam quality of the charge state booster. With optimized plasma and beam optics under the single-frequency heating regime, the maximum charge state of the 133Cs isotope produced was 27+, with the peak of the charge state distribution at Cs23+ with an efficiency of 8.5 %. However, with the implementation of two-frequency heating, the maximum charge state of Cs that can be produced increased to 32+, and the charge state distribution’s peak shifted to Cs26+ with an efficiency of 9.1 %. Additionally, the two-frequency heating resulted in a total beam RMS emittance that was approximately half of the one that was measured under the single-frequency heating due to the more pronounced negative potential dip created at the plasma center.
Design and commissioning of a versatile surface ion source
Authors: Saminathan S. , Ames F. , Angus T. , Baartman R. , Charles C. , Cho J. , Dirksen P. , Hruskovec T. , Jayamanna K. , Lovera M. , Marchetto M. , Minato B. , Schultz B. , Wager D. 
Published: May 2024

Abstract
A compact and versatile ion source was designed and commissioned to be used with the new low energy ion beam facilities at TRIUMF. The ion source is based on the principle of surface ionization, in which ions are generated from a neutral atom by impact with a solid surface. The design of the ion source considered several factors, including the type of ions, intensity, energy and emittance of the extracted beams from the source. Commercially available alkali materials with an ionizer are used in the source; the ionizer is integrated with the in house design of extraction and transport system. The source performance was characterized using diagnostics techniques, and its key parameters, such as beam current, emittance, and beam species, were measured. The results showed that the compact surface ion source is able to achieve high ionization efficiency and stable operation, and is suitable for use in commissioning and operation of various ion beam facilities in particle accelerator laboratories.
Performance increase for a medical proton beam ECRIS through dual frequency heating at MedAustron ion therapy center
Authors: Rockenbauer R , Schmitzer C S , Gambino N 
Published: May 2024

Abstract
The MedAustron facility, located in Wiener Neustadt, Austria, is a state-of-the-art synchrotron-based particle therapy center that provides irradiation with proton and carbon ion beams in an energy range of 62MeV to 252MeV and 120MeV/u to 402MeV/u, respectively. In order to improve on extracted current and on long term stability, key factors for medical accelerators, the dual frequency heating mode was tested at the source level. Through the use of dual frequency heating an increase in the intensity through the accelerator sections could be achieved, without changing the optics of the overall machine. The use of dual frequency heating has also improved the transmission efficiency from LEBT to LINAC section by 4 %. Across a wider range of input power, beam transmission is elevated when comparing to single frequency heating. As a result of this increased transmission, in room particle count could be improved in comparison to single frequency heating.
Design and Experiment of a Slotted Antenna Surface Wave Plasma Flood Gun
Authors: Cui Bujian , Peng Shixiang , Ma Tenghao , Jiang Yaoxiang , Wu Wenbin , Guo Zhiyu , Chen Jiae 
Published: May 2024

Abstract
In a modern ion implanter, plasma flood gun (PFG) is used to neutralize wafer charge during doping process, preventing the breakdown of floating wafers caused by the space charge accumulation. In order to obtain the PFG which can produce ribbon electron beams with the characteristics of high stability, high plasma density, no metal pollution and long life, studies at Peking University (PKU) are focused on surface wave plasma flood gun (SW-PFG) recently. A 2.45 GHz SW-PFG with a quartz plate and a series of metal slotted antenna arrays was designed and tested. Theoretical studies are carried out to optimize the SW-PFG structural parameters. The quartz plate thickness is determined as 15 mm. The size of the plasma chamber is 280 mm×150 mm×40 mm with a 280 mm×2 mm extraction slit. In the experiment, a relatively uniform argon plasma is obtained under the condition of gas flow rate of 2 sccm and input power of 800 W. In this case, the plasma distribution is studied by emission spectrum diagnosis and 73 mA ribbon electron beam is measured.
Research on slope algorithm based laser welding guidance technology for 3D vision inspection of thin-walled parts
Authors: Song Ning , Zhao Yuan 
Published: May 2024

Abstract
Visual guidance technology advances quickly and so do the technical requirements for weld trajectory, which needs to fulfill performance indices for high precision, anti-interference and quick processing. In this study, the approach of getting 3D point cloud data by directly scanning the workpiece to be welded with a 3D scanner is used because it is more precise and reliable than processing gray-layer data obtained from a depth camera, turning it into a 3D point cloud. The weld boundary is retrieved by slope calculation for the butt weld after preprocessing the three-dimensional point cloud data (cut, down-sampling, and abnormal value removal). The center point is then determined. After that, a welding trajectory is produced by fitting the center point, which is transmitted back to the actuator to guide its welding work and realize the identification and tracking of the weld.
Effect of Nb content on the microstructure and mechanical properties of CoCrNiNbx high-entropy alloy
Authors: Hong Jialin , Li Shuang , Zhang Li , Yang Jingmei 
Published: May 2024

Abstract
This paper systematically studies the effect of Nb content on the microstructure and mechanical properties of CoCrNiNbx (x=0, 0.2, 0.4, 0.6, 0.8) high-entropy alloy. The results show that the secondary Laves phases start to precipitate in the alloy when the Nb element content is 0.2%. With the increase of Nb content, the shape of secondary phases changes from punctate to elongated. The maximum yield strength of the alloy is 585.88 MPa when x=0.6%, and the maximum Vickers hardness of the alloy is 688.9 HV when x=0.8%, caused by the precipitation strengthening mechanism.
Study on mechanical properties of polyurethane mixtures with different fillers combined with industrial problems
Authors: Zhang Zixiong 
Published: May 2024

Abstract
This paper mainly introduces the classification of polyurethane mixtures. To produce new polyurethane composites used in manufacturing, the team researched Polyurethane combined with different composites and showed the mechanical properties of the composites on a chart. When reducing-graphene oxide (GO) and multi-walled carbon nanotubes are mixed with polyurethane, the composite can increase Young’s Modulus to 615 MPa and tensile strength to 657 MPa with a weight reduction of 5%. Glass fibre filled with Polyurethane also provides a fairly Young’s Modulus (over 10000 MPa) with a high weight percent up to 20%. How to increase the content of reduced GO and carbon nanotubes in polyurethane filling will be a problem worthy of further exploration.
Design of transmission mechanism of punch feeding and discharging manipulator
Authors: Han Leilei , Jiang Di , Niu Lei , He Qin 
Published: May 2024

Abstract
The press loading and unloading manipulator is a kind of intelligent equipment based on automation, which is specially developed for realizing the automation and unmanned production of the press shop. It can replace the worker’s work by implementing the manual editing program and greatly improve the efficiency of production and quality. The design optimized the traditional transmission scheme comparison and molded the structure based on the solid works modeling. The key supporting parts of the manipulator are analyzed by the finite element method. The simulation results showed that the manipulator can satisfy the designed loading requirements and guarantee the designed accuracy.
High-temperature flexural mechanical properties of SiC/SiC composites
Authors: Meng Yi , Yang Shengchun , Liu Xiaochuan 
Published: May 2024

Abstract
To assess the flexural behavior of SiC/SiC composites in high-temperature atmospheric environments, three critical influencing factors were identified: selection of fixtures, loading and supporting roller dimensions, and span-to-thickness ratio. Subsequently, through experimental methods and finite element model simulations, the impact of these factors was investigated. The study identified the most suitable fixture materials and configuration dimensions for SiC/SiC materials. It was found that as the span-to-thickness ratio increases, the flexural strength of the material continues to rise, reaching a turning point at 543 MPa, after which it decreases. The maximum interlaminar shear stress consistently decreases with an increasing span-to-thickness ratio. Combined with the failure mode analysis of the samples, it was observed that for a span-to-thickness ratio equal to or greater than 16, the sample failure modes are all valid. Additionally, regarding the observed non-linearity in the stress-strain curve when testing with a larger span-to-thickness ratio, it is recommended to apply a large deflection correction to the flexural stress.
Optimization of reliability and sensitivity analysis for flange structures
Authors: Gong Longjia , Feng Hanlin 
Published: May 2024

Abstract
The study delves into the reliability-driven optimization design of the flanges, drawing from reliability design theory, advanced optimization methodologies, and comprehensive sensitivity analysis. Flanges, integral to mechanical systems, demand precise design. Reliability design theory emphasizes consistent operation under diverse conditions. A novel approach to the flange-specific reliability sensitivity analysis method is central to this research. It promises to revolutionize flange design. By understanding the first two moments of core random parameters, we expedite reliability-driven optimization designs for mechanical connections. The programs enhance our approach, streamlining the pursuit of reliability-driven designs and providing rapid, accurate sensitivity analysis data for mechanical connections. This data offers critical insights into parameter influence, enabling targeted design adjustments. In summary, this research represents a significant advancement in mechanical engineering. By integrating reliability design theory with cutting-edge methodologies, it promises to enhance the quality and reliability of mechanical connections, meeting the rigorous demands of contemporary engineering applications. This holistic approach will play a pivotal role in the future of mechanical component design.
Kinematic analysis of inverted planetary roller screw considering skew error
Authors: Zhang Changhui , Fan Yuanxun , Zhang Ming , Xu Zhiwei , Yan Cheng 
Published: May 2024

Abstract
To reveal the motion characteristics of inverted planetary roller screws under the influence of axial deviation error, the working principle of inverted planetary roller screws was elaborated, and a motion analysis model of inverted planetary roller screws based on deviation error was established. This paper analyzed the angle error, axial displacement error, and relative velocity error of the roller, and comprehensively analyzed the influence of errors and parameters on the motion state.
Discussion on damage of type IV hydrogen storage cylinder
Authors: Yang Bo 
Published: May 2024

Abstract
Aiming at the judgment that the interface joints between different material parts of high-pressure hydrogen storage cylinders are prone to fatigue damage under repeated charging and discharging conditions, the progressive damage finite element model of nonmetal-metal-nonmetal multi-dimensional composite hydrogen storage cylinders is established. Thestress distribution and static strength of composite hydrogen storage cylinders are analyzed, and the influence law of winding composite technology on the stress distribution and static strength of composite hydrogen storage cylinders is studied.
Study on reliability of gold belt welding for Aerospace Microwave Circuit
Authors: Wang Qiongjiao , Fu Yonghui , Liu Jiangtao , Song Changxu , Li Ke , Zhao Yuxin 
Published: May 2024

Abstract
As a highly reliable and flexible interconnection method, gold belt welding is widely used in the interconnection of aerospace microwave circuits. In this paper, to reveal the influence of the technological parameters of gold belt welding on stress, the typical aerospace electronic equipment was studied by Ansys finite element software. The result shows that the stiffness consistency of two structures which are connected by a gold belt and the winding radius of the gold belt are the crucial factors in the reliability of gold belt connection. A process-strengthening measure has been proposed based on the analysis results. The verification of the process experiment shows that using EC2216 adhesive on both sides of a gold belt can effectively reduce stress and improve mechanical reliability. Furthermore, the analytical methods and measures have been extended to other flexible interconnection methods, which provide a solution to the highly reliable interconnection in the aerospace product.
A study on the strand arrangement in 3D printing of continuous carbon fiber composite materials with multiple strands
Authors: Zhang Xinghua , Zhang Fan , Zeng Lingwei , Tu Yiwen 
Published: May 2024

Abstract
3D printing of continuous carbon fiber composite materials with multiple strands has significant potential for improving model forming efficiency. However, in this field, we are faced with the challenge of arranging multiple fiber strands closely without excessive overlap consolidation, to avoid damage to the original model. The inability to effectively control the arrangement of multiple strands can significantly affect the print accuracy and mechanical performance of the model. Therefore, in this study, a predictive formula for the line width of carbon fiber strands is first presented. Subsequently, a device dedicated to 3D printing with multiple strands is designed using this formula, and the interrelationship between pressure and the arrangement of multiple strands is delved into. Comparative tests are also conducted on printed parts for tension and bending to investigate the influence of strand arrangement tightness on the mechanical performance of printed samples under different pressure conditions. Through electron microscopy experiments to analyze the microstructure of fracture surfaces, the causes of differences in mechanical performance and the potential effects of different pressures on print accuracy are explained. The results of the study indicate that when pressure can be precisely controlled to ensure a tight arrangement between multiple strands, the mechanical performance of printed parts reaches its optimal state. The tensile strength can reach 360.62 MPa, and the bending strength is 311.04 MPa. At the same time, for test samples printed under the optimal printing pressure, their surface accuracy is also at its best.