This study was performed to develop a nondestructive inspection system to detect grinding burn, which is capable of quantitative 100% inspection inside a production line. An eddy current sensor, which has advantages of short inspection time and low cost, was used. In the 1st report, we proposed a new technique for eddy current sensor to avoid misdetection caused by the dispersion of material properties of test pieces, and its effectiveness was confirmed. In this 2nd report, with the aim of practical application of the inspection system, the major measurement disturbances under common production line conditions were addressed. A Grinding Burn Detection System has been prototyped, and it was confirmed that quantitative inspection is indeed possible with no effect of disturbance.

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This paper explores the thermomechanical treatment consisting of shot peening and heating applied to carbon steel, and the effects on surface characteristics and fatigue characteristics. Shot peening was performed with an air-type machine using cast steel balls. Hardness and compressive residual stress in the re-shot-peened workpieces were measured. In all cases of re-shot-peened workpieces, maximum hardness was greater than that obtained in the initial process only. For all workpieces subjected to heat treatment, improvement of fatigue life was found in the workpieces subjected to initial processing only. The surface characteristics of the peened carbon steel were improved by heating and subsequent re-shot peening.

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The effects of microshot peening on the compressive residual stress of spring steel were investigated. The compressed air method was used for projection of microshots consisting of high-carbon cast steel and cemented carbide 0.1 mm in diameter. The workpiece used was commercial spring steel SUP10. The effects of variables such as shot velocity and peening time on compressive residual stress were studied. The surface layer of the workpiece was sufficiently deformed by microshot peening. Compressive residual stress was observed near the surface. At a large number of cycles to fracture, microshot peening could more effectively enhance the fatigue strength. The use of hard microshot, such as cemented carbide, was found to cause a significantly enhanced peening effect for high-toughness spring steel.

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This study deals with internal finishing of cooling channels in molding dies with free abrasive grains. Fluid flow in the cooling channel was simulated, and the influence of the internal face protuberance on the finishing performance of curvature channels was investigated experimentally. The results showed that the internal face roughness was improved significantly by the effect of spiral flow of the fluid. The application of face protuberance was effective for improving of the face condition in the cooling channel.

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An electrodeposited diamond wire tool is utilized for wafer-slicing of silicon, which is used as the baseplate of crystal-type solar cells. High-speed manufacture is one of the most important factors for manufacture of these diamond wire tools at low cost. In this study, a drum-type plating apparatus was developed that can plate diamond grains by electrodeposition on piano wire at high speed by controlling the relative speed between the piano wire and the diamond grains. A prototype of the diamond wire tool was manufactured using piano wire of φ120μm, and its plating and slicing abilities were evaluated. The results indicated the usefulness of the developed plating system to manufacture the diamond wire tool.

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In the light scattering measurement of the nano-scale defects on the surface of bare silicon wafer, detecting defects becomes so difficult that defects become small. It is because the signals from defects become weak and the influence of the noise from micro roughness becomes large relatively. In order to realize high signal-to-noise ratio detection, we propose the novel optical inspecting method using Gaussian spot illumination shift. It is the method of reconstructing scattering efficiency distribution of a sample domain including defects by carrying out computer processing using the distribution information of illumination, and the nano-shift of illumination. In this report, the validity of proposed method by the computer simulation was verified. The high signal-to-noise ratio result compared with the conventional technique was obtained in the simulation to the sample which has a defect with noise assuming micro roughness.

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