In this paper we discuss the removal of surface oxidation layer of permalloy 78 using Na₂SO₄ EO water (electrolyzed oxidizing water). First, we threw light on the etching efficiency of Na₂SO₄ EO water on the surface of Permalloy 78 by comparing it with the etching efficiency of soaking in H₂SO₄ solution and NaCl EO water. The comparative study showed that as for the etching efficiency on Permalloy 78, Na₂SO₄ EO water was superior to H₂SO₄ solution, while inferior to NaCl EO water. Next, we threw light on the influence on the surface micro shape of permalloy 78 by the SEM observations and AFM measurement. Lastly, by analyzing the surface, we made it clear that the performance of Na₂SO₄ EO water on removal of surface oxidation layer of permalloy 78. The results showed that as for the removal speed of surface oxidation layer on permalloy 78, Na₂SO₄ EO water superior to H₂SO₄ solution. By this study, we got the suggestion that Na₂SO₄ EO water can be applied to the surface processing of Permaooly 78.

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Electroforming is a major replication method for producing precise and complicated shapes. In industry, precise optical components and molds are produced by the electroforming process for a long time. Recently, this method has also been used in MEMS fields for mass production of the nanometer pattern. In this study, we focus on the electrodeposition condition to increase the replication accuracy. In order to remove the influence of thermal deformation from the replication accuracy, Ni electrodeposition under a room temperature condition is employed. The electrodeposition condition is optimized from the viewpoint of the internal stress. Then we developed the electrodeposition system which can remove the babble on an electrodeposited film perfectly by vacuum degassing. The results of the replication experiment of a mandrel indicate that the proposed condition will open new applications and devises in electroforming.

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Diamond materials are expected to be used as future substrates for power devices because they have excellent material properties, such as remaining stable at high temperatures and high resistance to chemical environments. On the other hand, etching and mechanical processing are very difficult because of the chemical and physical properties of diamond. As device materials must be polished without crystallographic distortion beneath a polished substrate, simplified planarization techniques accompanied with high surface quality are especially required. Ultraviolet rays excited polishing of single crystal diamond substrates has been studied in our laboratory, and the UV-assisted polishing characteristics, such as a higher polishing rate and superior final surface roughness, have been revealed. By using these polishing techniques, we can use diamond as a substrate material for future power devices because we are able to polish a mosaic wafer containing joined samples of two or more substrates, and minimize the occurrence of dislocation on the polished substrate. This paper reports the effective in diamond substrate for power device.

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A novel bump formation technology for tape automated bonding (TAB) packaging, in which bumps are mechanically fabricated on inner leads for TAB tapes using the micro-press technique, has been developed. A dome-shaped bump, 70μm diameter and 26μm height, is formed on an inner lead by compressing the lead between a combination of a rigid punch and a die. This Micro-Press Bump technology, enables reducing packaging costs drastically, because bump formation can be carried out with only one simple procedure, without using any additional materials, such as gold, except for the leads. A bump formation apparatus involving piezoelectric actuator, which has ability for a high bump formation productivity, as well as highly accurate bump formation, has been newly developed. By optimizing bumping conditions, such as punch and die shape and punch-die clearance, highly accurate bumps, ±0.5μm height accuracy, have been fabricated.

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In this study, a theoretical investigation on the Class A condition for planar curves is conducted. Here, the term “Class A” denotes high-quality curves and surfaces that have mainly been used for industrial products like automobiles. Although high-quality shapes play an important role in aesthetic design, its effective generating method have not been developed. Fundamental study on Class A curves have progressed recently; however, its condition is not sufficient and how to control this curve has not been presented sufficiently. Therefore, our method presented in this paper proposes an additional condition for creating Class A Bézier curve to produce high-quality shapes and also proposes a curve generating method and system to prove the usefulness of this method.

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The recent progress of laser scanners makes it possible to capture dense point-clouds of large-scale facilities. Large-scale facilities are mainly composed of many primitive surfaces, such as planes, cylinders, cones, spheres, and tori. However, it is not easy to reliably extract these surfaces from point-clouds because it is actually difficult to capture complete point-clouds of surfaces. In this paper, we discuss how to reconstruct pipe structures from insufficiently extracted surfaces. In our method, we first extract planes and cylinders, which can be reliably extracted, and detect the relationship among detected surfaces on a depth image. Then we estimate shapes and locations of various pipe structures using the relationships among surfaces. Finally we verify estimated shapes based on visibility tests and eliminate inconsistent structures. In our experiments, our method could sufficiently reconstruct pipe structures using only a single scanning data.

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To perform manufacturing tasks with sufficient accuracy, the position of the tool tip should be measured accurately. We developed a measurement system that detects the tool tip position by image processing. This study uses ray tracing simulations to examine the error in the tool tip position of square end mills versus the numerical apertures of the optical system used for illumination. The system consists of a telecentric illumination system and a telecentric imaging system. The diameters of the standard model for comparison and of the square end mill are φ0.1mm. The square end mill and an object used as a standard model were compared. For the standard model, the tool edge obtained by the simulation exhibits dilation relative to the original 3D model as the numerical aperture increases. This phenomenon causes refraction on the flat bottom surfaces of the standard model. On the other hand, for the square end mill, the tool edge obtained by the simulation exhibits erosion relative to the original 3D model as the numerical aperture increases. The absolute values of the errors are one-fourth those of the standard model because the bottom surface of the square end mill has a clearance angle.

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This paper deals with the cutting mechanism against cemented carbide by using a diamond coated carbide end mill. The influence of tool wear, cutting force, and machined groove integrity on the cutting of cemented carbide was investigated experimentally. The ball end mill with a diameter of 6mm was applied under the condition of air-blow supply. As results, the coated diamond film on the rake face was immediately flaked when the grooving length was less than 20mm. However, the cutting force was decreased by flaking the coated film, and the stable cutting was achieved without any damage to the base material of ball end mill until the grooving length was 800mm.

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