Improving water repellency of a metal surface is required in a wide range of industrial applications. In this study, the water repellency control of an oxygen-free copper surface was attempted by generating micro V grooves on the surface by using ultraprecision cutting technology. The results showed that the maximum contact angle of a water drop on a micro V-grooved surface could be as high as approximately twice that of a flat surface. The contact angle depended strongly on the direction, depth, pitch of the grooves, and burr formation at the edges of the micro grooves. A method for controlling burr formation was proposed.

Fine micro grooves of various depths and pitches were fabricated on brass surface by ultraprecision micro cutting, and the effects of groove geometry and orientation on surface wettability were investigated. Results showed that the contact angle of a liquid drop changes significantly with the depth and orientation of the grooves. By optimizing the grooving conditions, the contact angle was increased to about twice that of a flat surface. Effects of crystal grain boundaries in the workpiece material and effects of cutting conditions on burr formation during micro grooving were studied by both experiments and finite element simulation.

The evaluation structure of Finnish design professionals and laymen for interior wood were investigated following a previous study.As a result, the tendency of the evaluation structure was clearly divided by the design professionals and laymen in case of Finland. The features of the structure for the professionals were observed as calmness by the condition of grain pattern, added value for space by natural aging and versatility of wood. On the other hand, the features of the structure for the laymen were related to harmony with surroundings by familiarity of wood, modernity by novel color and safety by naturalness of wood. In a future study, a comparative study for the evaluation structure of both Japanese and Finnish design professionals and laymen will be conducted to examine the effective measures for utilization of domestic wood and guideline to design wooden architecture.