bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Microstructure and Property of the SHS Welding Joint
Authors: Yang Hui , Zhang Guo Dong , Fei Yuan Mei
Published: November 2012

With the self-designed welding powder formula,this experiment employed the SHS reaction to weld the base metal,which was steel Q235 here,then respectively used Olympus large-scale horizontal digital microscope to analyze the structure morphology of the welding seam's different regions,JEOL SEM to point-analyze and line-analyze elements' distribution near the the weld interface and HV-1000 CCD automatic measurement microscopic vickers hardness tester to measure the microhardness of the pure copper's welding seam.The experiment's result shows the hardness of different part of the welded joint varies largely,and that the join of alloy elements can increase the microhardness of the welding metal,and that the welding metal and base metal interdiffuse,grow and mix remarkably near the fusion line,realizing wonderful metallurgical bonding.
Study of Windscreen Angles on Car Characteristic
Authors: Bao Hai Tao
Published: November 2012

The aerodynamic problem is associated with the shape of the forebody and afterbody of a car. The finite volume method is used to discrete the governing equations, the second-order up wind difference scheme is adopted for the convection term and the centric difference scheme for the dissipation term. The comparison of pressures nephogram and velocity nephogram are presented among nine rear windscreen angles of the symmetry. Analyzing the result, The results show that the different angle of the rear window, the flow separation and re-attachment points for the different; the resistance coefficient is also different. It is proved that the numerical simulation air flow of passenger car is feasible. The conclusions of analysis provide the theoretical foundation for styling optimization of car, it is of certain guiding significance for practical application.
Research on Engine Fault Detection System Based on Exhaust Emission
Authors: Wang Cheng , Xu Shan Zhen
Published: November 2012

Vehicle exhaust composition contains running state information of the vehicle. Real-time detecting emissions ingredients of the vehicle can realize engine fault diagnosis. Based on the engine exhaust emission abnormal reason analysis, the design scheme of the hardware and software of the system was established. By using the neural network and virtual instrument technology, the software of the engine fault detection system based on emissions was developed. This system is not only to test the gas concentration that contained in automobile exhaust such as CO, HC, CO2, NOx, O2 in different working condition, but also to diagnosis the working performance and working state of the engine.
Teaching Transition for International Education from ‘Foreign Students Class’ to ‘International Class’: The Case of Materials Physics Courses
Authors: Duan Li Bing , Geng Wang Chang , Zhang Fu Li , Shi Xiao Long
Published: November 2012

Internationalization of higher education has become an irreversible trend of modern world, where international course is the key link. For Chinese universities, during the transition from traditional ‘Foreign students class’ (for foreign students only) to ‘International class’, in which Chinese students and foreign students will be trained under one roof, they have to face great challenges of teaching transition, including teaching contents, methods, examinations transformations. In this paper, taking materials physics courses for example, we put forward some suggestions on teaching transformation of international education from ‘Foreign students class’ to ‘International class’, basing on the experience of one-year visiting in University of Victoria (UVic), Canada and the differences of teaching between our Northwestern Polytechnical University (NPU) and UVic.
Study on Histocompatibility and Carcinogenicity of Silicone Gel-Filled Breast Implants after Radiation Sterilization
Authors: Yang Yang , Liu Fen Ju , Liu Qing Fang
Published: November 2012

Objective: To evaluate the histocompatibility and carcinogenic toxicity of silicone gel-filled breast implants after irradiation sterilization and promote the application of irradiation sterilization in the polymer biomaterials. Methods: The initial contaminating bacteria of silicone gel-breast implants were detected in accordance with ISO11737 standard, and the dose of irradiation sterilization was set according to ISO11137 standard. After irradiation sterilization, a series of tests included cytotoxicity, sensitization, intracutaneous irritation and implantation tests were performed to evaluate the histocompatibility of silicone gel-breast implants. Results: No cytotoxicity and carcinogenicity were observed in irradiation sterilized silicone gel-filled breast implants, silicone gel-filled breast implants after irradiation sterilization did not induce local reactions, sensitization, intracutaneous irritation. Conclusion: After the dose of irradiation sterilization, silicone gel-filled breast implants had a good histocompatibility and no carcinogenicity, radiation sterilization is a good method for medical polymer biological material, which deserves further promotion and application.
Optimization of Flow Shop Scheduling Problem Using Differential Evolution and Variable Neighborhood Search
Authors: Zhou Yan Ping
Published: November 2012

This paper proposed a new differential evolution algorithm based on variable neighbourhood search which is called as VNSDE. In VNSDE, the operation of variable neighbourhood search is performed after three basic operations of differential evolution, which can enhance the global search and improve the convergence. VNSDE is applied for solving ﬂow shop scheduling problem with the makespan criterion. Computational experiment is performed over a typical FSSP benchmark using VNSDE, GA and DE, and result shows that VNSDE has higher performance than GA and DE.
Mechatronics Education Curriculum for Nurturing Consumer Electronics Engineers Using LEGO Education Tools
Authors: Koh Keishin , Kanai Norikane , Misu Takayuki , Ohtani Masaki , Nakajima Yoshito
Published: November 2012

We developed a new mechatronics education curriculum for nurturing consumer electronics engineers that consists of eleven courses, divided into four grades, in which LEGO education tools were actively applied to various projects. During each of these courses, students are required to complete specific projects using various LEGO education tool components and kits. These projects included fabricating prototype consumer electronics products such as a CD player, a home security system, and an HEMS module. After four years of implementation, it was demonstrated that the planning ability, manufacturing sense, and creative power of students had been extended significantly.
Entropy-Enhanced Genetic Algorithm with Tabu Search for Job Shop Scheduling Problems
Authors: Huang Ying Jie , Yao Xi Fan , Ge Dong Yuan , Li Yong Xiang
Published: November 2012

By combining Genetic algorithm with Tabu search algorithm and adjusting crossover rate and mutation rate based on information entropy, a hybrid genetic algorithm was proposed for larger-scale job shop scheduling problems, and the benchmark instances were used to verify the algorithm with simulation. Simulation results show that the proposed algorithm can solve larger-scale job shop scheduling problems, and it has obvious advantages over traditional scheduling algorithms.
Attrition Milling of CNT and Dispersion in Mg Alloy Matrix by Friction Stirring Process
Authors: Yoo B.C. , Byeon Jai Won
Published: November 2012

Effect of attrition milling and subsequent ultrasonification of CNT on dispersion in ethanol was investigated. An attempt was also made to disperse the CNT in Mg alloy matrix by solid state friction stirring process for fabrication of metal matrix composite. Attrition milling was performed at a rotation speed of 700rpm for various times up to 6 hour. After 2 hours of milling, amorphous trace was observed in X-ray diffraction pattern. Attrition milling and subsequent ultrasonification enhanced dispersion of CNT in ethanol. Mg alloy matrix composite dispersed with the CNT was successfully fabricated by friction stirring process. The CNT-dispersed composite was analyzed by optical microscopy and Vickers hardness.
The Project of Automation of Synthesis of Fatty Acid Methyl Ester as an Additive for Diesel Fuel
Authors: Sroka Zbigniew J. , Kulazynski Marek , Kawalilo Paweł
Published: November 2012

As petroleum fuels are getting higher in price day after day. I is important to search for an alternative fuel as crude oil will not last forever specially in this high economical and industrial progress. In a parallel way engineers and scientists are searching for additives for the current known fuel until they find the best alternative fuel which has to fulfill the pollution and technical requirements. One of the solution is to implement the idea of downsizing engine fuelled with alternative biodiesel - in this case manufactured by the transestrification by using microwave heating. The process needs automation to keep control for manufacturing efficiency and quality of fuel properties. Authors show the automation layout and present equipment of test stand. There is short summary of combustion engine emission tests, too.
Mg-Induced Shift of Band Edge in ZnO:Mg Probed by the Visible Luminescence
Authors: Guo Shu Xia , Li Ji Wu
Published: November 2012

Mg-doped ZnO was synthesized using a co-precipitation technique. X-ray diffraction (XRD) measurements and absorption spectra show that Mg ions are doped into the lattice positions of ZnO. In the room temperature photoluminescence (PL) spectra, two emission bands, ultraviolet (UV) and visible, were observed. Either of two emissions shows a blue-shift. The visible emission band is composed of the green emission and the blue emission. The amount of blue-shift in green emission is 0.03 eV, about half of the amount of blue-shift in blue emission. Mg substitution raises and lowers conduction- and valence-band edges, respectively.
Study of Porous Hydroxyapatite/Chitosan Bioceramics for Bone Implantation
Authors: Wang Feng , Lai Qi Hui , Wang Mei Ting , Shen Jian Xing
Published: November 2012

hydroxyapatite/Chitosan bioceramics were fabricated by combining in-situ chemical synthesis and freeze drying method, using (NH4)2HPO4, Ca(NO3)2·4H2O, and chitosan(CS) as raw materials. The effect of freezing temperatures, solid loading and freeze-drying time on microstructures of hydroxyapatite/Chitosan bioceramics was studied. The microstructures of the fabricated porous bioceramics were investigated by means of Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The results showed that the hydroxyapatite/Chitosan bioceramics have interconnected porous structures from several microns to 200um, more suitable to bone tissue implantation. In addition, the porous structures are affected by freezing temperature.
TEM and STEM Electron Tomography Analysis of Amorphous Alloys CoP-CoNiP System
Authors: Mekhantseva Tamara , Voitenko Oleg , Smirnov Ilya , Pustovalov Evgeny , Plotnikov Vladimir , Grudin Boris , Kirillov Alexey
Published: November 2012

This paper covers the analysis of amorphous alloys CoP-CoNiP system by means of high-resolution transmission electron microscopy (HRTEM), scanning transmission electron microscopy and electron tomography. The last years have seen a sufficient progress in the analysis of nanomaterials structure with the help of high resolution tomography. This progress was motivated by the development of microscopes equipped with aberration correctors and specialized sample holders which allow reaching the tilts angles up to ±80°. The opportunities delivered by the method of electron tomography sufficiently grow when producing high resolution images and using chemical analysis, such as X-Ray energy-dispersive microanalysis and electron energy loss spectroscopy (EELS).
The Analysis of the Corrosion Parameters' Sensitivity of the Fractionator Overhead Recycle System
Authors: Fan Yu Guang , Piao Zai Dong , Chen Bing , Zhou San Pin
Published: November 2012

The relation model established by artificial neural network that includes 4 corrosive material parameters that are Cl-, H2S, NH3 and pH value and corrosion testing parameter that is Fe2+ of the fractionator overhead recycle system, studied the corrosion sensitivity of the corrosion parameters, has got the sensitive areas, put forward the suitable range of the corrosive material parameters of corrosion control in the production process.
Assessment of Blood and Tissue Compatibility of Dental Implant
Authors: Liu Jian , Yang Yang , Liu Fen Ju , Liu Qing Fang
Published: November 2012

To evaluate the blood and tissue compatibility of the dental implant samples, the whole blood clotting time, prothrombin time and partial prothrombin time, hemolytic rate and local implantation tests of the dental implant samples were determined, which will provide the basis for the clinical safety of such medical products. The WBCT, PT and PTT results showed that there were no significant difference (p> 0.05)between the testing groups and the negative control group, hemolysis rate of the dental implant samples was 1.38%, less than 5%, which in line with medical equipment blood compatibility test, all of these results indicated that the dental implant had a good blood and tissue compatibility.
Wafer Level Glass Molding
Authors: Hünten Martin , Hollstegge Daniel , Klocke Fritz
Published: November 2012

Manufacturing of micro optical components is approached with many different technologies. In this paper it is presented how the precision glass molding process is enabled to manufacture micro optical components made out of glass. In comparison to the existing glass molding technology the new approach aims for molding entire glass wafers including multiple micro optical components. It is explained which developments in the filed of simulation, mold manufacturing and molding were accomplished in order to enable the precision glass molding on wafer scale.
Advanced Machining Processes for Micro Mold Fabrication
Authors: Brinksmeier Ekkard , Riemer Oltmann , Robert Christian , Twardy Sven
Published: November 2012

This paper presents two alternative approaches in mold making for micro forming processes. The quality of formed micro parts is mainly dominated by the process parameters and the surface characteristics of the applied forming tools. Forming dies with advanced micro structures can improve the result of forming processes compared to tools with smooth surfaces. Here an approach of micro ball end milling is described to generate the macro geometry as well as an engineered surface texture on micro forming tools in one machining step. In addition to the surface topography, the die material has a decisive influence on the forming result and durability of the forming tool. Therefore single crystalline diamond represents an promissing material for forming tools, because of its unique material characteristics. On the other hand single crystalline diamond requires unreasonable high efforts for its geometrical shaping. Therefore, this paper will introduce a new approach to machine single crystalline diamond by thermo-chemical material removal.
Portable 532 nm Iodine-Stabilized DPSS Laser for Length Standard
Authors: Oozeki Hidekazu , Masuda Hiroki , Miyata Kaoru , Matsuura Toshiaki , Takahashi Tomotaka
Published: November 2012

A diode-pumped solid-state (DPSS) laser, such as a Nd:YAG green laser, has become smaller in size , lower in cost and higher in performance. Therefore, the DPSS lasers are widely used in many industries. For a laser interferometers and secondly length standards, stable light sources are in demand. We have developed 532 nm iodine-stabilized DPSS lasers used for the applications. The lasers have following features ; compact design (D 280×W 170×H 120 mm), high power (3 mW) , high stability ( < 1×10-10 : allann deviation k=1 at τ=1 sec), and easy operation.
Cutting Performances of Nano-Polycrystalline Diamond
Authors: Harano Katsuko , Sumiya Hitoshi , Murakami Daisuke
Published: November 2012

Single-phase (binder-less) nano-polycrystalline diamond (NPD) has been synthesized by direct conversion sintering from graphite under high pressure and high temperature. NPD is characterized by extremely high hardness compared with single crystal diamond (SCD), even at high temperature. In addition, NPD has high wear resistance, no anisotropic mechanical properties, no cleavages, and high thermal stability. These characteristics suggest that NPD has high potential for use in precision cutting tools for various hard works. In order to evaluate the cutting performance of NPD, cutting tests for various cemented carbides were conducted under various conditions and the results compared with those of single crystal diamond (SCD) and conventional polycrystalline diamond containing metal binder (PCD). The results revealed that NPD has outstanding potential for precision cutting and processing of diverse hard and brittle materials.
Fundamental Experiment of Near-Dry Deep Hole Drilling with BTA Tool - The Optimal Cutting Conditions and Tool’s Geometry
Authors: Nagata Fukuhito , Akashi Koji , Ishibashi Daisaku
Published: November 2012

The BTA tool is a tool for deep-hole drilling. The deep-hole which be machined by this tool has the excellent straightness and roughness. However, it's use a lot of cutting oil. Therefore, it will lead to environmental destruction. Thereupon, in this study, it is applied the near-dry system to the deep-hole drilling with BTA tool. In the previously, it was designed the experimental device with a double tube system, and the cutting experiments was carried out. In this system, the chip is discharged through inside of the inner tube. Frequently, the chip is cannot be divided by the adhesion on the cutting edge during drilling. Thereby, the chip was jammed into the inside of tool’s tube. It is tried experiments of various cutting conditions, cutting speed and feed rate, by tools with different geometry, height and width, of the chip-breaker. And, it is observed the discharge condition of chips, the chip’s shape and the situation of adhesion. As a result, it can be found the optimum cutting condition and tool’s geometry for a continuous chip’s discharge while the deep-hole is drilling by a BTA tool in near-dry system.
Temperature Measurement of Surface Grinding Using a Fluid Supplying System from inside of Grinding Wheel
Authors: Li Zhi , Yao Yasuhiro , Nakae Keigo , Sasahara Hiroyuki
Published: November 2012

In this research, the temperature rise of the machined layer during surface grinding using a fluid supplying system from inside of grinding wheel is measured. Compared with the conventional fluid supply from an external nozzle, the grinding fluid is expected to be reached surely to the grinding point if this fluid supplying system is used. Thus the amount of supplying fluid can be reduced keeping the comparable cooling efficiency. Two or more thermocouples are continuously set to the machining layer from its back side through the small hole. Then the temperature change was measured during the continuous reciprocating grinding (round trip) with small depth of cut. As a result, even if the amount of the grinding fluid supply is decreased to 0. 5 L/min, the temperature rise in the machining layer is not very different from the case that the supplying amount is 10 L/min. In addition, by the result of the series of the experiments, the relationship between the temperature rise of the machining layer and the state of the supply of the grinding fluid and the grinding energy is inspected.
Formation Mechanism of Grain Cutting Edges in Micro Dressing of Polycrystalline cBN Grinding Wheels
Authors: Ichida Yoshio
Published: November 2012

This paper presents a mechanism for the formation of grain cutting edges in the micro dressing of coarse-grain polycrystalline cubic boron nitrite (cBN) grinding wheels using a fine-grain diamond dresser. Many grain cutting edges having a flat surface consisting of ductile smooth surfaces as well as many brittle micro dents, are formed on the working surface of the coarse-grain (#80 mesh) cBN wheel by micro dressing using a fine-grain (#1200 mesh) diamond dresser. This result shows that the flat surfaces of cutting edges on the wheel surface are formed on the basis of a ductile removal process as well as a brittle micro-fracturing of cBN grains by the diamond cutting edges. Moreover, cylindrical grinding experiments with these wheel working surfaces were conducted to clarify the feasibilyty of creating a ground mirror-like surface. As a result, it was confirmed that high-quality mirror surfaces with roughness less than 0.03 m Ra can be efficiently formed using the working surface prepared by this micro dressing method.
Technical Performance of Zirconia-Coated Carbonyl-Iron-Particles Based Magnetic Compound Fluid Slurry in Ultrafine Polishing of PMMA
Authors: Guo Hui Ru , Wu Yong Bo , Li Ya Guo , Cao Jian Guo , Fujimoto M. , Jacobs S.D.
Published: November 2012

A kind of zirconia-coated carbonyl-iron-particles (CIPs), which show long-time stability against aqueous, is installed in magnetic compound fluid (MCF) to polish PMMA. Performance (normal polishing force and surface roughness) of zirconia-coated CIP based MCF slurry with different CIP concentrations is investigated. For comparison, the performances of the conventional non-coated CIP (i.e., HQ) based MCF slurry and MRF slurry in which DI-water is employed instead of MF are also examined. In the presence of Al2O3 abrasive particles, the use of zirconia-coated CIP based MCF slurry can not result in better polishing performances compared with conventional HQ CIP based MCF slurry; In the absence of Al2O3 abrasive particles, higher normal polishing force and smoother work-surface were obtained with the zirconia-coated CIP based MCF slurry rather than the MRF slurry; For the zirconia-coated CIP based MCF slurry without abrasive particles, the concentration of zirconia-coated CIP should be less than a certain value (in the current work, 70 wt. %), otherwise MCF slurry shows bad particle dispersion and is easily dried, resulting in the loss of its polishing ability.
Simulation Investigation Ultrasonically Assisted Grinding of SiC Ceramics with Single Diamond Abrasive Grain
Authors: Cao Jian Guo , Wu Yong Bo , Guo Hui Ru , Li Ya Guo , Fujimoto Masakazu , Ohmura Akira
Published: November 2012

The present work deals with the simulation investigation of chip formation in ultrasonically assisted grinding (UAG) of SiC ceramics with single diamond abrasive grain in order to reveal the material removal mechanism in UAG of SiC materials. In simulation, smooth particle hydrodynamic (SPH）method coupling FEM modeling is employed to overcome the large material distortions that occur in the simulation analysis of single point cutting process when only the finite element method (FEM) is used. The abrasive-grain is modeled with finite element while the target workpiece is modeled by SPH particles. The simulation results revealed that normal and tangential forces in UAG are smaller compared to those in conventional grinding (CG) without ultrasonic vibration. The scratch profiles shows that the cutting path appears to be sinusoidal when ultrasonic vibration is introduced in grinding process, which leads to a higher material removal rate than that without ultrasonic vibration.
Investigation of Particle Impact Phenomena in Powder Jet Deposition Process
Authors: Nishikawa Chihiro , Mizutani Koichi , Zhou Tian Feng , Yan Ji Wang , Kuriyagawa Tunemoto
Published: November 2012

Powder jet deposition (PJD) method is one of the blasting methods to generate surface coatings. The optimization of PJD conditions has been reported in our previous research. However, the deposition mechanism in PJD is still under investigation. Impact phenomena between an alumina particle with the mean particle size of 2 μm and a glass substrate has been successfully simulated by smoothed particle hydrodynamics (SPH) method. From the simulation result, we have deduced that a cubic particle is fractured by an impact, and it is adhered on to the substrate. It has been also deduced that substrate is removed by a spherical particle impact. Furthermore, PJD experiments of alumina particles blasted onto a glass substrate were also conducted. The particle size distribution of rectangular particles before and after impact was measured. It was found that the particle sizes after impact averagely became smaller than those before impact. The substrate was partly removed when spherical particles impact. From the results of the simulation and the experiment, we believe that the rectangular particles are fractured due to the impacts at the moment blasting onto the substrate, and then, firmly deposited on the substrate.
Effect of Ultrasonic Vibration Drilling on Cutting Stress Distribution
Authors: Isobe Hiromi , Uehara Yusuke , Hara Keisuke
Published: November 2012

A drill processing for the difficult to cut material such as ceramics, hardened steel, glass and heat-resistant steel is widely requested in the industrial world. Furthermore the drilling process becomes more and more difficult in the case of that the requested hole diameter is less than one millimeter. In order to achieve requirements for drilling process, ultrasonically assisted machining is applicable. Ultrasonic vibration assisted machining techniques are suitable to machine difficult-to-cut materials precisely. The ultrasonic vibration assisted sub-millimeter drilling process reduces the cutting forces and prevents severe wear of tools. However, it is difficult to observe directly the effect of vibration action because the process of ultrasonic drilling is dynamic instantaneous and micro cutting process. In this report, high speed camera with appropriately arranged polarized device realized the visualization of process of ultrasonic drilling based on the photoelastic analysis. For the conventional drilling, the stress distribution diagram showed the intensive stress occurred under the chisel and side wall. On the other hand, the ultrasonic drilling produced lower and stable cutting force and decreased the tool temperature.
Investigation of Cutting Phenomena in High Speed Ultrasonic Turning
Authors: Hara Keisuke , Hashikai Daisuke , Isobe Hiromi , Ishimatsu Jun , Take Yoshihiro , Koiwa Toshihiko
Published: November 2012

This study investigated phenomena of ultrasonic cutting in case of high speed conditions. Ultrasonically assisted cutting techniques were developed by Kumabe in 1950’s. He found “critical cutting speed” that limits cutting speed to obtain ultrasonically assisted effects and is calculated by frequency and amplitude of oscillation. In general, ultrasonically assisted cutting is not suitable for high speed cutting conditions because the effects of ultrasonically applying are canceled due to tool contacts with workpiece during cutting operation. Present ultrasonically assisted cutting cannot increase cutting speed because cutting speed is limited by above reason. And ultrasonically assisted cutting cannot improve productivity due to long processing time. We conducted high speed ultrasonic cutting, maximum cutting speed of this research was 160m/min which is higher than general critical cutting speed. Workpiece material is JIS SUS304 stainless steed and cemented carbide tool inserts were employed in this research. In ordinary cutting, generate terrible built up edge on to tool rake face. In case of low amplitude ultrasonic cutting, tool rake face hasn’t built up edge and periodically marks by ultrasonic oscillation were remained on the surface. Cutting phenomena of ultrasonic cutting is different compared with ordinary cutting conditions.
Development of a Novel Surface Processing System Using Femtosecond Pulse Train
Authors: Fukuta Yusuke , Hayashi Terutake , Michihata Masaki , Takaya Yasuhiro
Published: November 2012

When a laser pulse interacts with metal or semiconductor target, the coherent phonon, which is the coherent motions of lattice and molecule vibrations in solids, is excited by the interaction of electrons and high latitude electric field. It has unique properties of decaying in approximately several picoseconds and substance specific frequency. Owing to that, femtosecond laser processing is the local processing with little heat diffusion and little thermal damage to the target, due to the ultrafast time scales. We propose a novel femtosecond pulse ablation process with oscillation of the coherent phonon by femtosecond pulse train. The pulse train is shaped using Spatial Light Modulator (SLM), which shift the phase of the passing light. And coherent phonon oscillations are enhanced and decayed due to the controlling the shape of pulse train. It is able to activate the lattice motion for processing efficiently, and hence the target is expected to be ablated with high accuracy and less thermal damage.
Novel System Technology for Trepanning a Laser Beam at Arbitrary Developments of Angle of Incidence and Lateral Focus Position
Authors: Bechtold Peter , Mayer Godehard , Lühring Patrick , Schmidt Michael
Published: November 2012

In laser materials processing, trepanning optics are used to fabricate laser drilled holes of high aspect ratios (> 10) and controllable drill-hole conicity. However, trepanning optics available up to today are limited to circular trepanning geometries. Thus, only circular holes with drill-hole wall angles of rotational symmetry are feasible. Within this paper we will present a novel trepanning optic based on two piezo-actuatoric tip/tilt mirrors, being first of its kind, which allows arbitrary developments of propagation angle and lateral position of the laser beam, both being independent of each other. Consequently, the novel trepanning optic allows arbitrary drill-hole geometries such as circular, elliptical, rectangular etc. At the same time the drill-hole wall angle may be varied freely. Thus, asymmetric drill-hole wall angles are feasible such as tilt of the drill hole or wobbling of the drill-hole wall angle for instance. Demonstrative drill-holes of different shapes produced with an ultrashort pulsed laser prove the flexibility of the trepanning optic presented.
A Study on Driven-Type Rotary Cutting for Finish Turning of Carburized Hardened Steel
Authors: Kato Hideharu , Shikimura Tatsuya , Morimoto Yoshitaka , Shintani Kazuhiro , Inoue Toshio , Nakagaki Katsuhiro
Published: November 2012

Recently, cutting has replaced grinding in the finish processing of hardened steel. However, tool damage is a major problem in high-efficiency operations that use high-speed cutting and high feed rate conditions instead of the present cutting conditions. Therefore, the examination of a new cutting technique that can realize high-efficiency cutting is desired. In this study, the effects and efficiency of driven rotary cutting are investigated in the finish turning of carburized hardened steel. Based on the results, flaking occurs at the cutting edge at a short cutting length of 0.2 km using single-point turning. On the other hand, even if the cutting length amounts to 1.5 km, the tool wear width without flaking is small in the case of a driven rotary tool. Additionally, the tool wear is uniformly distributed along the circumference of the cutting edge. Furthermore, based on an examination of high-efficiency processing by increasing the feed rate, it is clarified that a feed rate of 0.3 mm/rev is the optimum condition from the viewpoint of wear resistance and surface roughness. Additionally, even if the cutting length amounts to 5.0 km for this condition, the flank wear width is as small as 0.04 mm, and the tool wear progresses gradually.
Material Removal Rate Control in Open-Air Type Plasma Chemical Vaporization Machining Using Optical Actinometry
Authors: Yamamoto Yuto , Hata Yuki , Hosoda Mao , Oshikane Yasushi , Yamamura Kazuya
Published: November 2012

Open-air type numerically controlled plasma chemical vaporization machining (NC-PCVM) is promising technique to fabricate the ultra-precision optical components and to finish the functional materials. The objective shape is fabricated by controlling the scanning speed of the localized plasma because removal volume is proportional to the dwelling time of the plasma on the workpiece surface. To achieve deterministic figuring with shape accuracy of nanometer level, it is essential to keep volumetric material removal rate (MRR) constant during and batch to batch processing. The removal rate is proportional to the density of fluorine radical generated by plasma. So, we control the electric power to keep the removal rate constant during the process based on the fluorine atomic density obtained by optical emission actinometry. We report the relationship between MRR and fluorine atomic density measured by optical emission actinometry.
Quadruple Stacked Elliptical Supermirror Device for One Dimensional Neutron Focusing
Authors: Nagano Mikinori , Yamaga Fumiya , Yamazaki Dai , Maruyama Ryuji , Soyama Kauhiko , Yamamura Kazuya
Published: November 2012

Focusing neutron beam with wide wavelength range is an indispensable technique used to compensate for weak signals from tiny samples in various experiments using pulsed neutron beam generated from high intensity proton accelerator facilities, such as J-PARC. Aspherical supermirror device is one of the most effective optical devices for focusing neutron beam with wide wavelength range since it has no chromatic aberration. Stack of aspherical supermirror enables us to focus neutron beams with wide divergence. Thin mirrors with a millimeter thickness are required to minimize the absorption loss of incident neutron beams since the thickness of a mirror shadows the reflective area of the other mirrors. Previously, we developed a fabrication process of a precise millimeter-thick elliptical supermirror. This process consists of noncontact figuring by the numerically controlled local wet etching technique, the finishing of surface without degrading mirror shape by low-pressure polishing, and the ion beam sputter deposition of NiC/Ti multilayers on both sides of the mirror substrate to compensate for film stress. In this paper, we report fabrication of elliptical supermirror with a thickness of 1 mm and development of multiply-arranged neutron focusing mirror device using stacked 4 fabricated elliptical supermirror with a thickness of 1mm.
A Simulation Study on Figure Error Correction Using Near-Gaussian Removal Function in Numerical Controlled Local Wet Etching
Authors: Shen Xin Min , Nagano Mikinori , Peng Wen Qiang , Dai Yi Fan , Yamamura Kazuya
Published: November 2012

Local wet etching (LWE) is a non-conventional deterministic surface figuring and finishing technique in ultra-precision optics fabrication fields. The general removal function in LWE is cylinder, so fringe of the removal function is sharp and scale of the removal function is determined by inner diameter of the nozzle head. When fabricating some specimen with high frequency figure error, ideal designed shape can’t be achieved easily. Compared with general LWE removal function, Gaussian removal function is more suitable for figuring owing to its smoother fringe and the centralization of its energy. At the same time Gaussian removal function can improve the efficiency in calculation of the dwelling time, because it’s very suitable for Fourier transform. What’s more, theoretical residual figure error can also be reduced for Gaussian removal function’s high spatial resolution. Ideal Gaussian function is difficult to obtain in LWE, so we have proposed near-Gaussian removal function by eccentric rotation of the nozzle head. Through controlling offset of the eccentric rotation, we achieve the optimal near-Gaussian removal function in LWE. Aims of the introduction of near-Gaussian removal function in LWE are to improve the fabrication efficiency and to remove the surface’s high frequency residual figure error.
Figuring of Aspherical Metal Mirror Substrate for Neutron Focusing by Numerically Controlled Electrochemical Machining
Authors: Tabata Takaaki , Nagano Mikinori , Yamazaki Dai , Maruyama Ryuji , Soyama Kazuhiko , Yamamura Kazuya
Published: November 2012

Neutron beam generated by high intensity proton accelerator facility is powerful tool to investigate characteristics of soft and hard materials. However, neutron beam is not major tool for material science since intensity of neutron beam is very weak compared to that of X-rays. Neutron focusing device is required to increase in intensity of neutron beam. Aspherical supermirror is effective for neutron focusing with wide wavelength range without chromatic aberration. In this research, we proposed a fabrication process for large and cost-effective aspherical mirror substrate made of aluminum alloy because metal can be figured coarsely at low cost by using conventional machining. The mirror fabrication process proposed by us consists of grinding for coarse figuring, numerically controlled electrochemical machining (NC-ECM) to correct objective shape with form accuracy of sub-micrometer level and low-pressure polishing to decrease in surface roughness to sub-nanometer level. In the case of figure correction of the mirror substrate by NC-ECM, deterministic correction is realized because NC-ECM is a non-contact electrochemical removal process for metal materials, without workpiece deformation. In this paper, we report fundamental machining characteristics of ECM, which uses electrode with a diameter of 10 mm and NaNO3 electrolyte.
Multiple Discharges Phenomena in EDM Using Electrostatic Induction Feeding Method
Authors: Feng Guang Lei , Yang Xiao Dong , Tian Kun , Wang Xue Zhi
Published: November 2012

In the micro EDM method by electrostatic induction feeding, a pulse voltage source is coupled to the tool electrode by a capacitor in order to reduce the minimum discharge energy per pulse. Positive pulse voltage and negative pulse voltage are applied to the tool electrode alternately, relative to the workpiece. In this study, it was found that when the feeding capacitance was large, multiple discharges occurred frequently during a single pulse duration of the pulse voltage source. Since the impedance of the pulse voltage source which was produced by the authors varied depending on the polarity, the multiple discharges occurred in the polarity with the higher impedance, while they did not occur in the opposite polarity. It was also found that when multiple discharges occurred, the discharge energy was released intermittently in the multiple discharges. In this study, using multiple discharges phenomena, better surface was obtained with higher removal speed.
Relationship between Magnetic Flux Density and Temperature Distributions of Permanent Magnets by EDM
Authors: Ichimura Yoshihiro , Takezawa Hideki , Mohri Naotake
Published: November 2012

It is difficult to machine permanent magnets by traditional machining such as turning, milling and grinding, because of magnetic force. However, electrical discharge machining (EDM), which is a non-contact thermal machining method, has been used for shape machining of magnetic materials. In the EDM process, non-magnetic materials such as copper and graphite are typically used for electrodes. Magnetic materials have a Curie point; therefore, their magnetic flux density reduces when they are heated to a high temperature. Because EDM is a thermal process, it has the potential to control the magnetic flux density of a machined surface. In this study, to clarify the relationship between magnetic flux density and temperature distributions in depth direction of permanent magnest by EDM, internal temperatures of magnets were investigated using a K type thermo couple during EDM. Neodymium magnets were used as work-pieces. The magnetic flux density of a machined neodymium magnet was measured. In addition, the effects of duty factor (D.F.) were also examined. The results showed that the average temperature inside of the magnet is determined by the input energy, depending on the discharge conditions. A decrease of surface magnetic flux density after EDM is affected by the magnitude of the area and the amount of decrease is due to the increase of the internal temperature of the magnet. Therefore, it isn’t determined by the magnitude of the simple input energy.
The Machining Characteristics of Insulating AlN Ceramics by EDM
Authors: Kaneko Kensei , Yamashita Ken , Fukuzawa Yasushi
Published: November 2012

AlN ceramic materials have high thermal conductivity and electrical insulation, prompting consideration of their use as a semiconducting material. Although AlN should be machined with a high accuracy of form and dimension to achieve products and components with requisite precision, mechanical and other machining methods such as the micro blasting technology or laser method cannot be used because of the brittleness and high thermal conductivity of AIN. Recently, we have succeeded in machining many insulating ceramics by EDM with the assisting electrode method. We have already machined many insulating ceramic materials such as Si3N4, ZrO2 and Al2O3. However, inferior machining characteristics were obtained with AlN than with other materials. In this study, the effects of several electrical discharge conditions were examined to obtain better machining properties, such as high material removal rate and a low electrode wear ratio. It was found that machining time decreased with an increase in capacitance, while the electrode wear ratio increased. In addition, the machining hole profiles were straight along the depth direction, and the shape of holes was non-tapered
Simulation of Contact Deformation Property of Digital Hand Skin and its Experimental Verifications
Authors: Xie Yu Lai , Kanai Satoshi , Date Hiroaki
Published: November 2012

The contact deformation of human skin is a significant factor in the virtual ergonomic assessment of handheld products, but previous works have neglected it or dealt with it in a simple way. In this paper, we propose a physical model of the contact deformation of human skin and, based on this model, present an efficient contact solving method to simulate the physical contact of the Digital Hand with product surfaces. The realistic contact deformation effect was realized, and we experimentally verified the estimated contact area, contact force and pressure distribution, and found the estimation results by the proposed model and the contact solving method well fit with the experimental data and the past data from the literature.
Study on In Situ Etching Rate Monitoring in Numerically Controlled Local Wet Etching
Authors: Shimozono Naoki , Nagano Mikinori , Tabata Takaaki , Yamamura Kazuya
Published: November 2012

Numerically controlled local wet etching (NC-LWE) is very promising technique for deterministic figuring of ultraprecision optical devices, such as aspherical lens, photo mask substrate and X-ray or neutron focusing mirror. NC-LWE technique is non-contact removal process using chemical reaction between etchant and surface of workpiece, so this technique enables us to figure the objective shape without introduction both substrate deformation and sub-surface damage. It is essential to measure temperature and concentration of the etchant to maintain the material removal rate constant over a processing time, since the etching rate of NC-LWE strongly depends on these parameters. Hydrofluoric (HF) acid solution is used as an etchant for synthesized quartz glass. We aim to develop an in situ monitoring system of etchant concentration using Raman spectroscopy and electric conductivity measurement. Raman spectroscopy measurement result indicates that there is a good linear relationship between HF concentration and intensity ratio of two specific Raman bands.
Improvement of Color Information in the Generation of 3D Models of Real Objects Using Range Intensity Images
Authors: Takahama Toru , Inomata Ryo , Terabayashi Kenji , Umeda Kazunori , Godin Guy
Published: November 2012

Texture mapping on scanned objects, which is the method to map color images on a 3D geometric model measured by a range image sensor, is often used for constructing a realistic 3D model. Color images are affected by the illumination conditions. Therefore, discontinuities of seams occur when simply applying texture mapping. In this paper, we propose a method for correcting the discontinuities using a range intensity image. A range intensity image is a kind of intensity image that is related to the reflectance ratio of the measured points, simultaneously acquired with a range image using an active range sensor. The method estimates the color information that is not affected by the lighting environment using multiple color images and a range intensity image. As a result, the method is effective to construct a 3D model with seamless color images. The effectiveness of the correction method is illustrated by experiments with real-world objects.
Method to Decide Paths and Postures of Flat End Mill for 5-Axis Control Machining Based on Minimum Cusp Height
Authors: Hokkyo Tatsuya , Aoyama Hideki , Sano Noriaki
Published: November 2012

Generally, ball end mills are used for free-form surface machining. When machining curved surfaces with large curvature change using ball end mills, it is necessary to use tools with larger curvature of the cutting edges than the maximum curvature of the surface and minute pick feeds or to change tools for fitting the curvature of one part of the surface. However this causes poor machining efficiency. The curvature of the cutting edge of a flat end mill can be fitted to the curvature of a point on machined surfaces by adjusting the tool posture. Therefore, flat end mills can efficiently cut almost all curvature curved surfaces without tool change. This paper proposes two methods for deciding tool posture and tool path for 5-axis control machining based on minimum cusp height. To decide the tool path, one method defines tool paths along isoparametric curved lines, while the other defines tool paths along curved lines along the minimum curvature direction. The basic system was constructed based on the proposed method, and the effectiveness of the proposed method was verified.
Proposal of Ball End-Milling Condition Decision Methodology Using Data-Mining from Tool Catalog Data
Authors: Kodama Hiroyuki , Hirogaki Toshiki , Aoyama Eiichi , Ogawa Keiji , Hukasawa Hiroaki
Published: November 2012

Machining is often performed by a machining center using various cutting tools and conditions for different shapes and materials. Recent improvements in CAM system make it easier for even unskilled engineers to generate NC programs. In the NC program, the end-milling conditions are decided by engineers. However, engineers need to decide the order of the process, cutting tool selection, and the end-milling conditions on the basis of their expertise and background knowledge because the CAM system cannot automatically decide. Data-mining methods were used to support decisions about end-milling conditions. Our aim was to extract new knowledge by applying data-mining techniques to a tool catalog. We used both hierarchical and non-hierarchical clustering of catalog data and also used applied multiple regression analysis. We focused on the shape element of catalog data and we visually grouped ball end-mills from the viewpoint of tool shape, which here meant the ratio of dimensions, by using the k-means method. We also found an expression for calculating end-milling conditions, and we compared the calculated with the catalog values.