著者

酒井 英樹

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.854, pp.17-00043-17-00043, 2017 (Released:2017-10-25)

参考文献数

16

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Sport riding performance on racing circuits and other locations is seen as an important element in the marketability of motorcycles. In sport riding, some riders start a turn while braking or start acceleration (driving) while turning. Furthermore, the braking aspect of sport riding performance is also critical to accident avoidance performance since it is similar to that of the braking during cornering performance. Consequently, in this paper a fundamental study was carried out to determine methods for improving the cornering limit performance during driving and braking. In the case of four-wheeled vehicles, the G-G diagram is used as a method to indicate the cornering limit performance. In the G-G diagram the longitudinal driving and lateral driving of the vehicle are set as the two axes. Therefore, the first part of this paper proposes a G-G diagram for motorcycles theoretically. In the latter part of this paper, this paper discusses the braking force distribution ratio of front wheel that would maximize the maximum lateral driving, the influence of the normal load distribution ratio of front wheel on the limit cornering property and the influence of the height of the center of gravity on it. From these result, this paper proposes methods for improving the cornering limit performance while braking.

著者

磯村 直道 藤原 大悟

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.854, pp.17-00013-17-00013, 2017 (Released:2017-10-25)

参考文献数

9

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Flight control system with position compensation applicable to trajectory tracking of agile maneuvers that require an attitude rotation and a reverse of main rotor thrust of single-rotor helicopters is proposed. The outer loop position compensator calculates the desired attitude and rotor thrust which reduce position tracking error by utilizing a kinematics equation established near the reference trajectory. The desired attitude is set using the magnitude of the rotor thrust in the reference trajectory, which enables continuous position feedback compensation based on the fact that the relationship between rotational and translational motion becomes independent as the rotor thrust decrease. To achieve high-bandwidth control of lateral-longitudinal angular rates in the inner loop, two-degree-of-freedom servo system is designed using a linear model with blade flapping motion dynamics. The control system is applied to autonomous control of flip maneuvers which include transition between upright and inverted hovering. The reference trajectory of a flip maneuver is generated as a parameterized simple equation which can be adjusted to the helicopter ability. Simulation and outdoor flight tests of the autonomous flip maneuvers demonstrated the capability of position feedback compensation that reduces position tracking error during out-of-trimmed flight state. This control technique can be extended to various agile flights for quick execution of flight tasks or recovery maneuvers from dangerous state.

著者

堀内 伸一郎

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.854, pp.17-pre04-17-pre04, 2017 (Released:2017-10-25)

著者

高橋 優輔 杉本 健太 日野 遥 橋本 成広

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.854, pp.17-00178-17-00178, 2017 (Released:2017-10-25)

参考文献数

10

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Control technique of orientation of a biological cell is expected to be applied to tissue engineering. It is known that morphology of the scaffold affects the cell behavior. For example, the micro stripe pattern can control cell orientation. The effect of aspect ratio of the micro checkered pattern on cell orientation has been investigated in the present study. The dimension of each unit of the micro checkered pattern is as follows: the length is 10 μm, and the height is 0.7 μm. Variation has been made on the width of the micro pattern: 5 μm (A), 8 μm (B) and 10 μm (C). Each type of repeated micro pattern was formed in the square area of 500 μm × 500 μm. The micro pattern was made of the negative photoresist material (SU-8 2) coated on a glass plate by the photolithography technique. C2C12 (mouse myoblast cell) was cultured for 24 hours on the micro pattern. The angle between the longitudinal axis of each cell and the width of the micro pattern was measured on the microscopic image. In each pattern, the average angle was as follows: 62.8 degrees on A, 50.2 degrees on B and 41.2 degrees on C. The experimental results show that the aspect ratio of micro checkered pattern controls cell orientation.

著者

高橋 優輔 吾妻 樹 溝井 篤志 日野 遥 橋本 成広

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.854, pp.16-00110-16-00110, 2017 (Released:2017-10-25)

参考文献数

19

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Separation technique of the circulating tumor cell (CTC), which would be a sample for diagnostics of cancer, is important. In the present study, a micro flow device, which has gaps between micro-cylinders, has been fabricated by photolithography technique to distinguish between cancer cells and red blood cells. Two kinds of cells were used in the test: Hepa1-6 and swine red blood cell. The mean diameters of two kinds of cells measured by ImageJ were 21 μm and 6 μm. Variation was made on the dimension of the gap: 10, 15, 20 and 25 μm. The micro cylindrical pattern was fabricated on the slide glass with a photomask of titanium film. The negative resist material (SU-8) was coated on the glass plate to make the 60 μm height of the micro cylindrical pattern. A micro flow channel was made between the glass plate with the micro cylindrical pattern and the flat polydimethylsiloxane (PDMS) disk. Swine blood was diluted 100 times by the saline solution. The concentration of Hepa1-6 was adjusted to 5000 cells/ml by the physiological saline solution or by the swine blood. The cell suspension of 30 μl was injected into the channel by a micropipette, and the trap rate at the gap of the micro pattern was measured. The experimental result shows that trap rates of micro cylindrical pattern gap of 10, 15, 20 and 25 μm are 100, 80, 37 and 26%, respectively. Most of the swine red blood cells can pass through the 10 μm gap. The result shows that the microchannel device developed in the present study is effective for the separation of the CTC.

著者

田丸 雄摩 清水 浩貴

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.854, pp.17-00278-17-00278, 2017 (Released:2017-10-25)

参考文献数

9

被引用文献数

1

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Non-contact supports involving air or magnetic forces are used as guide supports for linear motion mechanisms. In the present study, non-contact supports are generated using the effect of the static pressure force produced by a squeezed air film. The linear slider is supported at just two of its ends. Applying a different excitation amplitude to the two transducers leads to a difference in the floating height at either end of the slider due to the different air-film thicknesses. This causes the slider to tilt, which produces a propulsion force due to the dead load. An experimental apparatus with a flat plate slider was developed and its floating characteristics were examined. In addition, the propulsion force was measured for sliders with different weights. The results indicated that the floating height was 2 to 3 times the excitation amplitude. The slider was capable of travelling all over the movement stroke. The traveling force increased with increasing slider weight, and was about 0.15-0.35 mN. The measurement results were in good agreement with theoretical calculations. Thus, the present study showed that the slider could be successfully supported in a non-contact state and was capable of movement under the influence of a propulsion force generated only by the dead load.

著者

東﨑 康嘉 松下 直矢 隅谷 悠司 後藤 卓也 田中 智之

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.854, pp.17-00272-17-00272, 2017 (Released:2017-10-25)

参考文献数

13

被引用文献数

1

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Power transmission systems using gears require both large capacity and miniaturization. As a result, the gears used in power transmission need to be strong enough to withstand high loads and high engine speeds. Because surface damage and temperature are related, it is very important to know the surface temperature of gears in operation. However, measuring the surface temperature of gears in operation is difficult. As an effective means to measure the surface temperature, method of using dissimilar metals is known. The voltage proportional to surface temperature was produced by contacting dissimilar metals. This is known as Seebeck effect. The authors tried to use two simple ferrous metals. In this study, S55C (Carbon steel) and SUS316 (Stainless steel) were selected to dissimilar metals. Both dissimilar metals were heat-treated and surfaces were hardened. SUS316 was performed plasma carburizing process and S55C was performed induction hardening. As for the gear, it is known that the two or more teeth will mesh simultaneously. In order to remove the influence of the number of tooth in operation, the gear of two sheets were made into the one structure meshed by turns (combined lacked gear). When making the gear of two sheets into one structure meshed by turns. The experiments were operated on maximum condition of contact pressure 1.47GPa in a pitch point. As a result, surface temperature measured almost successfully by combined lacked gear by SUS316 plasma carburizing process and S55C induction hardening. When we compared the experimental values and the theoretical values using Blok's formula, surface temperatures on gear teeth values were largely same.

著者

志鷹 拓哉 村島 基之 梅原 徳次 月山 陽介 新田 勇 上坂 裕之 鄧 興瑞

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.854, pp.17-00252-17-00252, 2017 (Released:2017-10-25)

参考文献数

8

被引用文献数

1

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This paper addresses a novel lightweight and low starting torque bearing with looped carbon fiber brush (LCFB). LCFB simulates bristle of living being. Moreover, the static friction coefficient is nearly equal to the kinetic friction coefficient. By applying LCFB to a slide bearings, where a shaft is supported by multiple LCFBs, it is realized low starting torque bearings as well as lightness compared to conventional ball bearings. In this paper, we manufacture prototype LCFB slide bearings. With the bearings, we compare friction torque between LCFB slide bearings, slide bearings and deep groove ball bearings. As results, the ratio of starting torque to regular torque of LCFB slide bearing is from 0.93 to 1.07 which is smaller than that of the slide bearing. When micro-spline shaft is used as a mating material of LCFB slide bearing, the torque reduces because of decrease of real contact area between LCFB and mating materials. In addition, since LCFB utilize elastic deformation of fibers, LCFB slide bearings are not endurable in heavy radial load as high as load rating of ball bearing. Therefore, we define the load capacity of LCFB slide bearing from buckling load of a carbon fiber bundle to avoid overload state. We propose the load capacity as a design guideline of LCFB slide bearings.

著者

坂本 二郎 小林 佳介 北山 哲士 清水 信孝

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.854, pp.17-00212-17-00212, 2017 (Released:2017-10-25)

参考文献数

27

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An optimum design method for determining the cross-sectional sizes of thin steel plate columns used for steel framed house was developed to maximize their buckling strength under a constraint of constant volume using evolutionary computing and cold forming. Buckling analysis was performed by finite strip method (FSM) that can analyze the buckling loads of local, torsional, and total buckling within less computational time. Differential evolution (DE) was used for the optimization algorithm because it is a fast and reliable method for non-linear, non-convex, and multimodal optimization problems. In this research, an optimum design method is proposed, which combines DE and FSM to achieve an efficient global optimum design considering comprehensive buckling modes. This method was applied to overcome the optimum design problems of the thin steel plate columns with a lip channel cross-section. Normal axial compression capacity (Nc) of the column under a constant volume was maximized by considering design variables such as web height, flange width, and lip length of the cross-section. The search performance of the optimization method was evaluated by obtaining an objective function (1/Nc), which was calculated at the lattice points of the design variables. The optimum design point obtained by the optimization method included a global minimum point of the objective function surface, hence ensuring the validity of the proposed method. Furthermore, the optimum design problem was solved under the deformation constraint by considering connection to the wall panels for the column length of 1000 mm, 2000 mm, and 3000 mm. Optimum designs with the open profile cross-section was obtained for all the abovementioned column length. The optimum designs obtained by the proposed method can be used for practical purposes because of their open profiled cross-section and can be produced by cold forming.

著者

酒井 忍 北出 侑也

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

pp.17-00225, (Released:2017-11-15)

参考文献数

17

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Ball shooting machine (pitching machine) is used for practicing ball sports, and it is widely prevalent. However, there are few pitching machines that can throw a ball with a gyro spin, such as a football or rifle bullet, in which the axis of the ball spins in the same direction as the ball travels. In this study, a new ball shooting machine, which can throw in the ball in a wide range of speeds and all pitch types (no, top, down, side and gyro spin balls) was invented by introducing a launch mechanism using four rollers (two launch and two gyro rollers). The shooting machine is able to arbitrarily change the rotational speed of the four rollers and the crossing angle of both gyro rollers. Shooting tests were conducted using the prototype shooting machine to confirm the ability of its performance. From the experiment results, the prototype machine had a maximum ball speed of 42.5 m/s, a spin rate of exceeding 5000 rpm, and a ball of any pitch type could also be shot. In addition, the position accuracy (shot accuracy) at the targeted fall position in the opponent's court was high because the gyro spin and other pitch types (no, top and side spins) were less than 140 mm and 40 mm (the diameter of one table tennis ball), respectively. The prototype machine had the necessary launching performance for table tennis practice of a college student level.

著者

石川 諭 近藤 孝広 松崎 健一郎 榎元 啓允

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.80, no.814, pp.DR0166-DR0166, 2014 (Released:2014-06-25)

参考文献数

10

被引用文献数

1

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A pressure wave generated by a compressor propagates in an air-conditioner piping system and causes a noise problem. The flow condition in the air-conditioner piping system becomes often a one-component two-phase flow, and attenuation of the pressure wave in the one-component two-phase flow is larger than the two-component two-phase flow because of the effect of the mass transfer. It is also important for the safety of nuclear reactors to understand the characteristic of pressure wave problems in the one-component two-phase flow. In this paper, we propose a concentrated mass model to analyze the pressure wave problems in the one-component two-phase flow. This model consists of masses, connecting springs, connecting dampers, and nonlinear base support dampers. The connecting spring and the connecting damper are derived from the compressibility of the gas phase and the effect of the mass transfer when the phase-change occurs. And the nonlinear base support damper is derived from the pipe friction. Additionally, an experiment on an air-conditioner piping system is performed, and the experimental results are compared with the numerical result in order to confirm the validity of the model. The numerical computational results agree very well with the experimental results. Especially, the attenuation of the pressure wave generated by the phase-change is numerically reproduced. Therefore, it is concluded that the proposed model is valid for the numerical analysis of the pressure wave problem in the two-phase flow.

著者

尾形 和哉 柳川 洸哉 大嶋 和彦

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.853, pp.17-00194-17-00194, 2017 (Released:2017-09-25)

参考文献数

8

被引用文献数

1

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Gyro actuator is often used for the posture control of systems which cannot be supported on a fixed ground. The gyroscopic moment makes preccesion movement of the gimbal mechanism and its effect depends on the rotating speed of the wheel. In this paper, the accurate dynamic model is derived for bicycle with twin gimbal mechanism considering ups and downs of the ground, which causes the disturbance to the bicycle. It turns out that the effect of the undulations of the ground is cancelled if the rotating speed of the wheels of the twin gimbal are exact the same. Then the stability of this model without feedback control is discussed. This model has fourth order characteristic polynomial and the characteristic roots for the first and the second modes are derived through lower order approximation. The first mode is unstable and the second mode is stable if there is a viscous friction in the gimbal rotation axis bearing. Simulation and experimental results show that the parameters should be designed so that the amplitude ratio of the gimbal pitch angle with regard to the cart roll angle for the first mode may become small to keep the posture of the bicycle for a longer time. This analysis method can be used for a simple feedback control system of the bicycle to evaluate the design parameters of the mechanism and control.

著者

吉原 拓実 志垣 俊介 倉林 大輔

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.853, pp.17-00108-17-00108, 2017 (Released:2017-09-25)

参考文献数

19

被引用文献数

1

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Searching an odor source is a challenging task for a distributed autonomous mobile robot due to the complexity of odor formation in the air. Because the shapes of odor plumes highly depend on the environmental conditions including dynamical changes of wind direction, a robust performance of searching is highly demanded. In this paper, we introduced an olfactory active sampling device that was equipped electronic fan to generate air current and suction olfactory information to the sensors. Our main contribution was proposing and evaluating adaptive sampling strategies for appropriate odor-searching behavior in real environments by using the device. The active sampling device was designed after observations of the wing-flapping-effect of a male silkworm moth, which corresponding to‘ sniffing ’of mammals. The device was composed of an electronic fan, two (left and right) gas sensors embedded in air ducts, and was attached to a mobile robot. Each duct had a flange so as to take the air in front of a robot effectively, and the electric fan attached on the end of the duct excluded odors incoming from the rear. We settled different environmental conditions in which the fluctuation of the air flow was changed. We conducted experiments to verify the feasibility of the adaptive sampling system. As a result, under most of the environments, the robot with active sampling showed better performance than that without active sampling. However, the result showed that optimal active sampling has environmental dependency. To realize more adaptive system, we suggested that it is necessary to change the activeness of inspiration depending on the situation.

著者

髙橋 新吾 中村 哲夫 有馬 祐杜 橋本 秀紀 中村 壮亮

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.853, pp.17-00035-17-00035, 2017 (Released:2017-09-25)

参考文献数

9

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This paper proposes an electrocardiogram (ECG) measuring system which simultaneously enables the reduction of input impedance and low-frequency cutoff through virtual amplification of the coupling capacitance formed by body capacitance and ECG electrode. This virtual amplification of the coupling capacitance is realized by the additional circuit which controls the inflow of external current to create the situation as if the time constant of the capacitance has increased. Moreover, not only this additional function but the amplification circuits commonly used in ECG measuring system has also been perfectly tuned-up. Here, instead of using the MOS-FET which shows bad noise characteristics, the combinations of J-FET differential amplifier and current feedback circuit have been used for stable amplification. In addition, coupling capacitors of the system are removed due to the DC-Coupling enabled by using single operational amplifiers instead of instrumentation operational amplifiers.

著者

松永 充弘 中澤 和夫

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.853, pp.17-00016-17-00016, 2017 (Released:2017-09-25)

参考文献数

20

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In resent year, the demand for the autonomous mobile robots which can navigate indoor environment, such as office room, warehouse, hospital has increased. Autonomous mobile robot needs some information to navigate various environment. Self position is one of the important information since the robots need to determine its any behaviors such as path planning. Unfortunately this information is including some critical error such as odometry error which is caused by wheel slipping and uncertainty of its model parameters. Scan match is one of the method to overcome this problem. By determining two point cloud data measured by sensor (such as LIDAR) mounted on robot at different measurement point, it can estimate such errors. And furthermore, scan match is used to improve the proposal distribution of Rao-Blackwelized Particle filter using grid map. However, the computational cost of scan match is higher because searching nearest neighbor need a large amount of computational resources. To overcome this problem, we propose high efficient scan match method, using likelihood field map and hill-climb approach. And then we also propose efficient likelihood mapping method concurrently. In our experiments, efficiency of our scan match method was higher than two conventional method, ICP and correlative matching. And it verified that our likelihood field mapping method efficiency has been improved.

著者

阿部 有貴 小笠原 亮大 尾崎 功一

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.853, pp.16-00572-16-00572, 2017 (Released:2017-09-25)

参考文献数

15

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This paper discusses a micro manipulation considering that an approach angle on pickup affects adhesion and mechanical balance on release by using two needle-shaped end-effectors. In micro-scale, adhesion is generated by capillary, van der Waals and electrostatic besides gravity. Accurate and repeatable pick-and-release/place of micro sized objects is a long-standing challenge due to the strong adhesion in micro manipulation. We first introduce a strategy of pickup and release of a micro sphere. The strategy features in that the approach angle on pickup decides release by two conditions: one is geometrical condition between the sphere and a tip of end-effector, and the another is mechanical condition by forces (adhesion, gravity and friction) to the sphere from the tip and a substrate. To confirm the efficacy of the strategy, the micromanipulation tests with different approach angles have been conducted. Finally, we show the experimental results by pickup and release of spherical glass beads and not spherical pollens, for confirming the validity of the proposed strategy as a novel manipulation method.

著者

川添 裕三 橋本 英樹 森上 修 村瀬 英一 古川 純一

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.853, pp.17-00159-17-00159, 2017 (Released:2017-09-25)

参考文献数

8

被引用文献数

1

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To explore the behavior of near-extinction flamelets in turbulent premixed flames, emission intensities of OH, CH and C2 radicals of hydrocarbon-air premixed flames have been examined using the newly developed emission spectroscopy system. It has been shown in our previous study that the emission intensity ratio of 515.5 nm/470.5 nm bands of C2 radical uniquely depends on the temperature of unstrained methane/air and propane/air flames. In the present study, to establish the technique that estimates the temperature of the near-extinction flamelet of turbulent premixed flames, the relation between the temperature and the emission intensity ratio of 515.5 nm/470.5 nm bands of C2 radical of strained flames has been sought by using a counter-flow burner. The unique relation between the flame temperature and the emission intensity ratio of 515.5 nm/470.5 nm bands of C2 radical has been found to exist for the Propane-air and the Butane-air strained flames. Therefore, it can be concluded that the temperature of flamelets of the Propane-air and the Butane-air turbulent premixed flames can be estimated by using the relation between the temperature of the strained flame and the emission intensity ratio of 515.5 nm/470.5 nm bands of C2 radical obtained in the present study.

著者

古口 日出男 佐藤 広美 前川 富哉 Chonlada Luangarpa

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.853, pp.17-00198-17-00198, 2017 (Released:2017-09-25)

参考文献数

15

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Singular stress and electric displacement fields occur at the vertex of interface in piezoelectric joints under an external loading. It can be expected that concentrated electric displacements causes large electric fields in an adjacent space and electric potential will be induced on the surface of electrode when the electrode approaches to the electric field. In the present paper, a piezoelectric joint which four blocks of piezoelectric material are bonded using a resin is analyzed. In this joint, a singular field occurs at a center gathering four vertexes in blocks and the intensity of singularity in electric displacements around the center of cross section in the joint may be four times larger. The intensity of singularity is numerically investigated using several methods for analysis to pursue the possibility of application of the singular fields. Firstly, three loading conditions, e.g., compression in the poling direction, compression in the vertical direction of side surface and input a voltage, are investigated for increasing a response of electric displacement in the piezoelectric joint. In the case of compression in the vertical direction of side surfaces, the maximum response is obtained. Hereafter, the results in the analyses are obtained for the compression of vertical direction of side surface. It is shown that the intensity of singularity depends on a power law of the thickness of adhesive layer. Influence of material properties of adhesive layer, piezoelectric and dielectric properties in the block of the joint, on singular fields is also investigated. It is shown that when piezoelectric materials with large piezoelectric constant are used, amplified electric displacements are obtained.

著者

國分 朋之 祖山 均

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.853, pp.17-00190-17-00190, 2017 (Released:2017-09-25)

参考文献数

24

被引用文献数

1

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Peening techniques are used to introduce the compressive residual stress into the surface of metallic materials in order to improve the fatigue properties. The fatigue crack propagation is affected by many factors in surface modification layer, however, the effect of these factors on the fatigue crack propagation is not clarified in detail. In this study, the fatigue crack propagation behavior in surface modification layer of duralumin treated by various peening techniques including shot peening, cavitation peening and laser peening was investigated. The relationship between the fatigue crack propagation behavior and mechanical properties was also evaluated. The fatigue crack propagation behavior varies depending on peening techniques despite the condition of the same peening intensity, since the mechanical properties in surface modification layer are changed with the peening techniques. The compressive residual stress σR and Vickers hardness HV are the important factors about fatigue crack propagation, however they do not show a correlation with the number of cycle to failure of the specimen Nf. Therefore, the new indicator combined with four factors i.e. σR, HV, full-width at half maximum β and maximum height roughness Rz were proposed. It revealed a significant correlation with Nf, and possibility to evaluate the effect of suppression of fatigue crack propagation by peening.

著者

佐藤 運海 川久保 英樹

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.853, pp.17-00179-17-00179, 2017 (Released:2017-09-25)

参考文献数

14

被引用文献数

1

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This paper discusses the surface modification processing of kovar alloy (Fe-29.72wt%Ni-16.28wt%Co) by Na2SO4 electrolyzed oxidizing water (hereinafter referred to as EO water). First, the etching effect of Na2SO4 EO water on the surface of kovar alloy was clarified by comparative experiments of chemicals and NaCl EO water. The comparative study showed that as for the etching effect on the surface of kovar alloy, Na2SO4 EO water was superior to H2SO4 solution, but inferior to NaCl EO water. Next, by the observation using SEM image, the influence of Na2SO4 EO water on the surface shape of kovar alloy was clarified. The results indicated that when using Na2SO4 EO water, the surface of polished test pieces which had not been heat-treated becomes smooth, but in the test pieces surface which had been heat-treated, a lot of dimples had occurred. When using the supersonic together with one of Na2SO4 EO water or NaCl EO water, the surface shape became smooth. Lastly, as for the test pieces after heat treatment, the surface oxidation layer removal experiment by the immersion was carried out. The results showed that Na2SO4 EO water could remove the surface oxidation layer like H2SO4 solution approximately. However, thin surface oxidation layer might be formed when using Na2SO4 EO water. By this study, we received the suggestion that Na2SO4 EO water could be applied to the surface treatment such as the etching of kovar alloy.