This study examined the characteristics of machined surface layer by end milling-burnishing method of 304 stainless steel on the vertical machining center. Hardness and residual stress of the finished surface subjected to the end milling-burnishing process under conditions of cutting speed Vc = 20 m/min, feed rate f = 2μm/tooth, and radial depth of cut Rd= 5μm were markedly improved compared to the non-machined surface before end-milling. Micro-Vickers hardness test on the finished surface indicated obtained hardness of 469 HV at the highest value. In addition, the residual stress of the finished surface after the end milling-burnishing process was improved to - 1191 MPa. Here, the relationship between cutting conditions and surface integrity was examined experimentally to elucidate the characteristics of the machined surface layer.

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Sliding materials are required for improvement of tribology characteristics. Surface texturing has attracted attention due to costs and environmental burden. In this research, a textured surface on chrome molybdenum steel was processed by the wet blast technique. Spherical zircon particles of three sizes were used as impact particles. The friction behavior of textured surfaces was investigated by a ball-on-plate reciprocating friction tester. The results indicated that the surface texture obtained by the wet blast technique using particles with an average diameter of 34.2μm had a low friction coefficient in the initial-test region, and the friction coefficient was stable in the end-test region.

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An adaptation of information entropy theory was proposed to evaluate the abrasive grain distribution over a wide range for the abrasive grain fixed tool face. To confirm the effectiveness of the proposed method, a model was developed with changes in abrasive grain number and distribution by simulation. The results indicated that the entropy value increased as the number of abrasive grains increased. Therefore, to evaluate dispersion in abrasive grain distribution, specific entropy was proposed. The proposed method can evaluate the relative distribution state of abrasive grains, even when the numbers of abrasive grains and distribution are different. From the results, the relations between the abrasive grain distribution on the belt, cutting ability, and tool life in actual belt grinding were clarified by information entropy. Furthermore, results with different behavior of entropy were compared, and it was indicated that the specific entropy fluctuates for a belt with long life.

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In the high-efficiency grinding process using a CBN wheel, it is necessary to minimize the amount of wheel removed by truing (hereinafter referred to as truing amount) to reduce tool costs. In this study, the relation of surface roughness and grinding resistance was investigated when the tip of the abrasive grain's cutting edge was removed in submicron order (hereinafter referred to as submicron removal) to reduce the truing amount. The results confirmed that the surface roughness is small while suppressing the increase in grinding force by reducing flattening of the tip of the cutting edge and the increase in number of cutting edges by submicron removal compared to conventional truing.

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