A5031137969- Metal and Thin Film Mechanics
- Metal Forming Simulation Techniques
- Diamond and Carbon-based Materials Research
- Advanced Surface Polishing Techniques
- Metallurgy and Material Forming
- Semiconductor materials and devices
- Advanced Machining and Optimization Techniques
- Microstructure and mechanical properties
- Surface Treatment and Residual Stress
- Microfluidic and Capillary Electrophoresis Applications
- GaN-based semiconductor devices and materials
- Nanofabrication and Lithography Techniques
- Advanced machining processes and optimization
- Microfluidic and Bio-sensing Technologies
- Adhesion, Friction, and Surface Interactions
- Microstructure and Mechanical Properties of Steels
- Ion-surface interactions and analysis
- Tribology and Lubrication Engineering
- Carbon Nanotubes in Composites
- Neuroscience and Neural Engineering
- Electromagnetic Effects on Materials
- Plasma Diagnostics and Applications
- Boron and Carbon Nanomaterials Research
- High-Velocity Impact and Material Behavior
- Laser and Thermal Forming Techniques
Tokyo Metropolitan University
2015-2024
Japan Society for the Promotion of Science
2024
Linköping University
2016-2021
University of Illinois Urbana-Champaign
1991-2018
Daido University
2015-2016
Industrial Research Institute of Shizuoka Prefecture
2015
Daido Steel (Japan)
1992-2008
Sumitomo Electric Industries (Japan)
2002
Tottori University
2000
Innovative Technology and Science (United Kingdom)
1982
Ti0.5Al0.5N alloy films, typically 1.5 μm thick, were grown on MgO(001) at temperatures Ts between 400 and 850 °C by ultra-high-vacuum reactive magnetron sputtering in pure N2. Films ≂480 560 single crystals which the lattice misfit strain was partially relieved glide of 〈001〉 dislocations, with Burgers vector =a0/2〈011〉, {011̄} planes. Cross-sectional transmission electron microscopy investigation showed no evidence residual extended defects films until thicknesses ≂150 nm point threading...
PVD technologies, including vacuum arc evaporation and DC-magnetron sputtering, have been utilized in industrial settings since the early 1980s for depositing protective coatings. These coatings encompass a range of materials such as metal nitrides, carbonitrides, oxides, oxynitrides, DLC, serving diverse applications cutting forming tools, automotive components, decoration. Vacuum generates highly energized ionized particle flux toward substrate, while “classical” gas-ion-dominated direct...
Abstract High power impulse magnetron sputtering (HiPIMS) is an ionized physical vapor deposition technique, providing a high flux of metal ions to the substrate. However, one disadvantages for industrial use this technique reduced rate compared direct current (dcMS) at equal average power. This mainly due target back-attraction probability with typical values in range 70%–90% during pulse. In order reduce effect, we focused on contribution ion fluxes available immediately after each HiPIMS...
Efficient metal-ion-irradiation during film growth with the concurrent reduction of gas-ion-irradiation is realized for high power impulse magnetron sputtering by use a synchronized, but delayed, pulsed substrate bias. In this way, stress-free, single phase α-W thin films demonstrated without additional heating or post-annealing. By synchronizing bias to metal-ion rich portion discharge, tungsten ⟨110⟩ oriented crystal texture are obtained as compared ⟨111⟩ orientation using continuous At...
As an approach to enhance the tribological performance of diamond like carbon (DLC) coating films for dry microforming operations, present study applied micro-textured structures DLC films. Micro-texturing was realized by using stainless steel wire mesh as a masking during ionized physical vapor deposition (I-PVD) Tribological fabricated with width 40 and 80 μm interval 30 were evaluated ball-on-disk type friction tester. To simulate severe contact state operation, normal pressure 1.2 GPa...
Low-temperature epitaxial growth of refractory transition-metal nitride thin films by means physical vapor deposition has been a recurring theme in advanced thin-film technology for several years. In the present study, 150-nm-thick HfN layers are grown on MgO(001) reactive high-power impulse magnetron sputtering (HiPIMS) with no external substrate heating. Maximum film-growth temperatures Ts due to plasma heating range from 70 150 °C, corresponding Ts/Tm = 0.10–0.12 (in which Tm is melting...
A simple and cost effective approach to stabilize the sputtering process in transition zone during reactive high-power impulse magnetron (HiPIMS) is proposed. The method based on real-time monitoring control of discharge current waveforms. To conditions at a given set point, feedback system was implemented that automatically regulates pulse frequency, thereby average power, maintain constant maximum current. In present study, variation waveforms over wide range gas flows frequencies HiPIMS...
Conventional ultrasonic-assisted forming in macro scale has been studied widely for decades. However, ultrasonic dynamic impact effect, which only occurs micro-scale, never thoroughly. The purpose of this study is to investigate and identify the influencing parameters amplitude vibration time ultrasonic-induced stress reduction considering effect. As first step purpose, commercially pure aluminum 1100 with specimen size 2 mm diameter height were selected compression tests varying press...
Abstract The ionization region model (IRM) is applied to a high power impulse magnetron sputtering discharge with tungsten target. IRM gives the temporal variation of various species and average electron energy, as well internal parameters such probability back-attraction sputtered species. It shown that an initial peak in current due argon ions bombarding cathode After peak, W + become dominating remain end pulse. We demonstrate how contribution total at target surface increases increased...
Abstract In the micro bending process, thinner foils may indicate larger springback due to size effect of strain gradient. Heat-assisted is an effective process reduce and improve accuracy products. order investigate mechanism behavior pure titanium under elevated temperature, experimental numerical analysis were carried out for different thickness (0.02, 0.05, 0.1 mm) with same hardness. The results show that angle decreases increasing temperature. experiments, it observed increases...
To investigate the underlying mechanism of effects surface texturing on lubricated sliding friction in metal forming operation, an in-situ observation system using transparent silica glass dies and a high speed recording camera was newly developed. correlate dimensional parameters micro-dimple textured structures tribological properties performed during bending with ironing process stainless steel sheet thickness 0.1 mm. The lubrication behavior were compared between different lubricant...