This paper describes the influence of NaCl EO water (electrolyzed oxidizing water) on the surface of Permalloy 78. First, the etching efficiency of NaCl EO water on the surface of Permalloy 78 was made clear by comparing it with the etching efficiency of soaking in HCl solution. The comparative study showed that as for the etching efficiency on the surface of Permalloy 78, NaCl EO water was superior to HCl solution. Also, NaCl EO water can process an etching equally to each composition elements of Permalloy 78 compared with HCl solution. Next, by analyzing the surface, the influence which NaCl EO water exerts on the chemical composition in the surface of Permalloy 78 was made clear. The results showed that NaCl EO water does not have any bad influences on the chemical composition of Permalloy 78. By this study, we got the suggestion that NaCl EO water can be applied to the surface processing of Permalloy 78.

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The renormalized particle molecular dynamics (MD) proposed in the first report has been applied to uniaxial tensile fracture simulations of a bar of mono-crystalline copper in the following way : First, the validity of the quasi-static MD to be used in the proposed method has been verified by comparing the result of the quasi-static MD with that of the standard MD. Then, the high-speed tensile fracture simulations by the proposed method have been carried out, recursively, such that the yield and fracture strains obtained by a simulation is used to modify the parameter between the particle interactions and a new simulation is carried out using both the modified particle interaction and the prescribed description method of particle motions. The repetition of this procedure produces the results for models whose sizes increase in powers. The results show that the fracture mechanism changes from ductile tearing to brittle shearing and to locally expanded breakage with the increase of the size of the model and thus with the increasing effect of stress waves. Finally, the method to embed the proposed method into continuum mechanics simulations is described.

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A soft EHL analysis model of Chemical Mechanical Polishing (CMP) is developed in the present study. Since a surface of a polishing pad is filled with micro asperities due to conditioning, the polishing pad deforms in a nonlinear manner by contacting to a wafer. A viscosity of the polishing pad also affects stress concentration beneath the edge of the wafer. In order to take into account both effects, damping behavior of the polishing pad and macroscopic characteristics of the polishing pad asperity deformation are considered at the same time in the proposed analysis. Based on the traditional contact model, i.e., Greenwood-Williamson model, nonlinear elasticity of the surface asperity layer of the polishing pad is formulated, and Arbitrary Lagrangian-Eulerian (ALE) method is applied to deal with dynamic structure analysis. A series of three-dimensional EHL analysis was conducted using the proposed model. Effects of viscosity of the polishing pad and the nonlinear elasticity caused by the polishing pad asperities on distributions of contact stress and fluid pressure were examined. Analytical results indicated that both distributions greatly depend on the viscosity and the nonlinear elasticity of the polishing pad, and thus the consideration of nonlinear viscoelastic behavior in the pad-wafer contact is important to predict the polishing pressure distribution, especially beneath wafer leading edge.

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In order to research effect on the cutting performance for aluminum alloy by mixing isopropyl alcohol (IPA) and water, the performance of IPA aqueous solution was compared with IPA and water by the sliding test, cooling test and cutting test. Consequently, it was found out that IPA aqueous solution provided the best cutting performance in the cutting fluids. The sliding test between aluminum alloys revealed that IPA aqueous solution has a function that suppresses the adhesion of aluminum alloy. It seems that the adhesion on the tool decreased by this function. The cooling test of heated test pieces showed that the cooling ability of IPA aqueous solution was higher than that of IPA. Because of high cooling ability, the chip in cutting with IPA aqueous solution mist might curl smaller than that in cutting with IPA mist.

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Authors have been developed a novel polishing method for silicon carbide substrate using functional fluids which are dispersed abrasives with silicone fluid. Behavior of abrasive can be controlled with electric field. In this report, we have confirmed the improved polishing rate in proportion to electric field strength, and the change for slurry characteristics by the solvent viscosity. And, we considered the improvement mechanism factor for polishing rate using controlled slurry under AC electric field in viewpoints of the number of active abrasives in polishing and the electric attractive pressure between polishing pad and workpiece.

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To automatically generate and update a machining database for feature based process/operation planning, a generating and updating method of a machining database based on Numerical Control (NC) data analysis is proposed. As the content of the database, the ISO 14649 machining information which consists of machining feature, machining operation, machining strategy, cutting tool and cutting conditions is derived from NC data, a cutting tool model and a rawpiece model. To derive the machining information for a machining feature, the tool paths are split according to their geometrical characteristics of the tool path, and a machining feature is derived from the machining process model which is generated from a split tool path, a cutting tool model and a rawpiece model. A machining operation for a machining feature is identified as roughing or finishing operation based on the geometrical relationship between the machining process models. A machining strategy is extracted from a split tool path based on tool motion pattern. As the cutting conditions, spindle speed and feed rate are derived from S and F code of NC data. The example of generating ISO 14649 machining information from NC data using the proposed analysis method is shown.

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A study on the life distribution and reliability of ball bushes composed of the sample sizes 52 set for standard products and 67 set for abrasive flow processed products are carried out by using the two-parameter and the three-parameter Weibull distribution function, and the lognormal distribution function for analyzing the test data. The basic dynamic load rating formula standardized by ISO in 2004 was also compared with the life test data in relation to the effect of crowning on both ends of the outer sleeve race. This study revealed the following : (1) The best fit for the life test data is achieved by the three-parameter Weibull distribution function introduced the minimum life γ as the third parameter with a constant Weibull slope of m=10/9. The lognormal distribution function comes second and the two-parameter Weibull distribution function the last. (2) The test data does not fit for the two-parameter Weibull distribution function with a normalized Weibull slope m=10/9, which has been used for the standard of ISO point contact rolling bearings as well as linear bearings. (3) Fatigue failure due to flaking on the ball bush is always initiated at the edge portion of outer race for standard products and near the rounded out portion of the edge of outer race for processing products. (4) Basic dynamic load rating increases by abrasive flow processing and λb_m factors are obtained by λb_m=1 for standard products and λb_m=1.2 for processing product, respectively. (5) It is found that the λb_m factors for the update test samples per the products of the later in 1970's are 1.83 for standard product and 1.86 for processing product, respectively.

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Lure fishing and fly-fishing have been positioned as sports deliberately different from the traditional Japanese fishing-style. In the case of fly-fishing, casting is the element which anglers must master in order to cast a fly, done so by using the weight of a line. This study uses experimental and computational analysis to investigate the dynamic behavior of a fly line. Fly-fishing is constituted by various elements, but the importance that casting holds is extremely large. Fling speed, the casting process and the loop shape of the line while in flight are important for the proper presentation of flies. Moreover, the shape of a fly line is also important for a long cast or controlled cast. Therefore, the most suitable casting method will be clarified from the viewpoint of sports engineering and human dynamics. There are some types of casting techniques, overhead cast, side cast, false cast (forward cast and back cast), double haul cast and roll cast. In the case that there is an obstacle something like a tree, anglers can not do back cast while the false cast. In such situation, anglers have to select “Roll cast”. Roll cast consists of only forward cast. The arms motion of roll cast is different from the motion of forward cast. Therefore, the initial condition at the time anglers start the roll cast is important for the appropriate casting. In this paper, a rod, a line and arms are modeled by using rigid bodies and links. The time history behavior of the model is calculated by pseudo angler velocity of the arms. The difference of the arms motion between forward cast and roll cast is evaluated. And the line behavior with respect to the initial condition that anglers start casting is clarified.

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