In this study, the effects of particle size for peening on microstructural changes in steel were investigated. To clarify the mechanism of grain refinement during peening in terms of kinetic energy of shot particles, the microstructures generated by fine particle peening (FPP) and conventional shot peening were characterized. The results indicated that FPP generated fine grains under lower energy conditions in comparison to conventional shot peening. This was because the kinetic energy per dent area on the specimen surface was increased with increasing amount of shot particles due to decreasing shot particle diameter. These results indicated that it is highly significant in generating fine grains to perform FPP.

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The wafer slicing process is one of the manufacturing processes for semiconductor devices, and a descent-type multi-wire saw is used for large workpieces in this slicing process. This type of multi-wire saw is excellent with regard to productivity and processing accuracy. However, it is difficult to supply slurry directly to the part being processed. This study was performed to determine the most suitable method for slurry supply in processing of a cylindrical workpiece by descent-type multi-wire saw. Specifically, the phenomena occurring in the processed part was observed using cylindrical Pyrex glass.

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This paper deals with three components of grinding forces related to the incidence of cracks to determine appropriate drilling conditions for smaller cracks, higher processing efficiency, and longer tool life in through-hole drilling of soda-lime glass plates. The crack propagation direction is estimated from the action direction of three components in drilling of glass plates using an electroplated diamond tool. In the drilling process, the components of the x-axis and y-axis increase gradually, and then decrease gradually to zero after piercing a hole at the exit surface. The component of the z-axis increases immediately at the start of drilling, and decreases gradually by the end of drilling after piercing a hole. The component of the z-axis increases with smaller grain size. Thus, the tool approach depth is shallow when the hole pierces. The crack size of the pierced hole is influenced by the component of the z-axis. On the other hand, the crack size of the formed hole from piercing the hole to the end of drilling is influenced by the grain diameter between the tool end and the cylindrical body.

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A method for turning micro shafts less than 1 mm in diameter was developed to establish a machining system. A linear relationship between thrust force and depth of cut under conditions of controlled approach angle was also confirmed in experiments. The empirical equation to estimate the thrust force was derived by applying this method. The suggested equation derives a method to keep thrust force at zero for the microshaft turning operation. The physical significance of this equation is discussed, and its relevance to physical properties was investigated. The experimental results confirmed that there are linear relationships between the coefficients of the empirical equation suggested here and Vickers hardness of the workpiece.

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