This paper discusses the basic characteristics of electrolyzed oxidizing water of dilute Na₂SO₄ and the etching effects on the surface of metals. First, the structure and the characteristics of the electrolyzed oxidizing water producing system as well as how electrolyzed oxidizing water of dilute Na₂SO₄ is produced by it are described. The electrolyzed oxidizing water producing system used in this study is the one with three tanks. Next, the relation between the characteristic value of electrolyzed oxidizing water and the value of electrolyzed electrolytic-current is investigated experimentally. How the characteristic value of electrolyzed oxidizing water changes as time passes is also investigated in the same way. Lastly, using the result of the experiment on the etching of pure iron material, the oxygen-free copper material and the alloy of copper and nickel, this paper elucidates the characteristics of electrolyzed oxidized water of Na₂SO₄.

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In filament winding method, there are two methods called DRY method and WET method. WET method uses fiber and resin, and DRY method uses a resin-impregnated carbon fiber, tow prepreg, in manufacturing. In general, the burst strength of CFRP made by DRY method is lower than that by WET method. In the present study, tow prepreg is wound on the simultaneously heated liner. This heated liner helps the resin to soften up and spread. And this phenomenon is expected to improve the burst strength of CFRP pipes. In this study, the volume fraction of CFRP was measured with combustion method and the burst strength of CFRP pipes was calculated and measured. In the volume fraction measurement, the void volume fraction of CFRP with simultaneously heated liner is less than that without simultaneously heated liner, and the burst pressures calculated based on measured volume fraction data were hardly affected by volume fraction. But, actually measuring the burst pressure, it was greatly affected and improved by using simultaneously heated liner. As a result, it was found that the burst pressure improves by using simultaneously heated liner and is affected by filament winding method and resin content in tow prepreg.

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The stability of jetting is a major requirement for industrial inkjet heads. Air bubbles entrapped in a piezo-driven inkjet head can occasionally cause jetting failures. The piezo actuators can be used as sensors to detect the acoustic influence caused by air bubbles. As in our previous paper, we developed a controllable bubble generation method by focused THG Nd:YVO₄ laser with the secondary Bjerknes forces and could intentionally generate bubbles from about 5 micron to 150 micron in radius at the designated point near the nozzle inside the inkjet heads.
In this paper, experimental results on the relationship between the electric signal from the piezo actuators and bubbles are presented. We find the existence of a kind of a dead zone where the emitted sound pressure from a bubble is insensitive to the bubble size. Our numerical study shows this phenomenon is attributed to the increase of the radiation impedance with an increasing bubble size in reverberant sound fields as in the inkjet heads. We also present CFD simulation results using models with a bubble inside an inkjet head in order to make an estimate of the bubble size and position to cause jetting failures.

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For oxide-CMP process in semiconductor manufacturing, which requires high precision, Run-to-Run control has been developed. The Run-to-Run control is a kind of repetitive control to adjust polishing time at every start of lot work in a work sequence. Film-thickness is controlled based on a process model, which expresses the relation between polishing time and polished thickness. In this paper, process model for oxide-film CMP with ceria slurry and the Run-to-Run control method in high volume manufacturing is described. In this CMP, relationship between polished thickness and polishing time is nonlinear. Control calculation is found to be concise by using a variable, which is film-thickness before CMP divided by removal-rate, for polishing-time correction. Parameters in the model are estimated with two steps to evaluate controllability. Run-to-Run control simulation is applied in order to determine the best parameter set, which achieves the largest process capability index Cpk. A result of high-precision film-thickness, whose Cpk is 1.39, is obtained.

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This study aimed at development of nano-level image storage with nanoscopic additional processing by using an atomic force microscope (AFM) probe as tool and glass as added material. It investigated about an influence which humidity has to tool wear, and a theoretical formula for predicting the amount of tool wear which took humidity change into consideration was proposed. The volume of tool wear calculated from this theoretical formula agreed with the experimental value well, and the cause in which additional processing in low humidity is possible by increasing processing normal load was clarified. By using the diagram obtained from the theoretical formula, selection of efficient additional processing conditions became easy.

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The relationship between the grinding conditions and AE wave in constant-cut surface grinding was considered for the purpose of examining the cognitive technology of a situation of grinding. Grinding of fine-ceramics generally advances by a brittle fracture. This report was considered the processing model of constant-cut surface grinding based on the Vickers hardness test. And, the amplitude of AE was formulated based on two kinds of cracks generated from this processing model. It was predicted that the amplitude of AE wave and the chip coefficient are a correlation. Some grinding experiments were conducted in order to examine the validity of the calculation formula. As a result, although some problems remained, relationship between the grinding conditions and the amplitude of AE wave was clarified. From this result, the guidelines which predicts the situation of grinding using the amplitude of AE wave was acquired.

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In the polishing process, it is pointed out that both the removal rate and accuracy of the polishing characteristics are affected by the actual contact conditions between the silicon wafer and a polishing pad. Additionally, it is found that the geometric characterization of polishing pad surface texture have a substantial influence on the actual contact conditions. In the previous study, we proposed a new measurement and evaluation method for polishing pad surface texture based on the contact image analysis method using image rotation prism. We have presented the effective measurement parameters in the previous paper that are (1) contact ratio, (2) number of contact points, (3) spacing of contact points and (4) spatial FFT result of a contact image. This paper presents the relationship between these parameters and polishing characteristics. The removal rate of polishing efficiency is measured by a series of polishing test. Polishing accuracy is obtained applying SFQR and ROA method. As a result, it is found that the proposed parameters are efficient in estimating polishing characteristics. Especially, the spacing of contact points and spatial FFT parameters that indicate high correlation results with the polishing characteristics.

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This report presents a two-dimensional monitoring system for precise process control of end milling processes involving the use of a small-diameter tool. The system enables the measurement of tool deflections and cutting forces in two directions : the cutting or tangential direction and the feed or normal direction. The use of this system to measure periodic change in tool deflection during a given turn is also presented. In an experiment, this system was applied to the end milling of a steel plate at different cutting speeds, depths of cut, and feed rates. Results indicated that this system enabled the in-process monitoring of tool deflection and the measurement of cutting force. They also demonstrated that the tool deflection and cutting force increased with the feed rate and depth of cut. Results of the in-process measurement of tool deflection suggest that the periodic change in tool deflection during a given turn is related to the rotation angle of the tool and the number of tool edges. These results also suggest that two-dimensional information and information on the periodic change in tool deflection with changes in the rotation angle must be taken into account when monitoring tool behavior and tool breakage.

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