This study proposes an in-process discrimination method of grinding state based on temporal transition of temperature information by focusing on characteristic temperature information for each rotation of the grinding wheel. A processing state monitoring grinding wheel with an embedded thermocouple that is capable of measuring the in-process grinding wheel surface temperature was used. Here, the characteristic temperature information means "temperature upon start of measurement," "maximum temperature," "descending gradient from maximum temperature," and "temperature upon completion of measurement" for each rotation of the grinding wheel. This study demonstrated that the possibility of abnormal grinding state can be determined in an in-process manner by evaluating the characteristic temperature information, which changes depending on the type of grinding wheel specifications and processing conditions, and further, by monitoring the time-oriented transition in such temperature information.

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Mirror-surface generation of Zr-based bulk metallic glass (BMG) by cutting operations using a single-crystal single-point diamond cutting tool is investigated. In preliminary experiments, orthogonal cutting for inclined workpiece of BMG was carried out. Measured profiles of the groove showed good agreement with the profile of the cutting tool. Cutting forces during turning operations were measured under different cutting conditions. Furthermore, visualization tests of chip formations were performed using a high-speed camera. Based on the preliminary test resutls, cutting conditions were chosen carefully for mirror-surface cutting of BMG. A mirror surface of BMG with 16 nmRa was then successfully obtained by the cutting operation.

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Precision machining techniques have a number of serious problem, such as tool interference against complicated machining shapes and improvement of accuracy in processing. To resolve these issues, we suggest the Superconductive Assisted Machining (SUAM) method, which involves application of a magnetic levitation tool using the pinning effect of superconductivity during polishing processing. The SUAM method can eliminate tool interference because machining shape is determined by movement of the magnetic levitation tool during processing. Here, we measured the holding force, such as attractive and repulsive forces, from the pinning effect of superconductivity. The results indicated a maximum attractive force of 4 N with an initial magnetic levitation tool height of 9 mm. In this case, the holding force was dependent on the initial distance between the magnetic levitation tool and the superconductor bulk. In addition, we evaluated the dependence of polishing pressure and rotation frequency on polishing rate using fixed abrasive polishing pads. The results indicated that the polishing removal rates increase with increasing polishing pressure and rotation frequency.

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