| 摘要 |
PROBLEM TO BE SOLVED: To prevent a scribing tool from becoming unusable at an early stage.SOLUTION: A scribing tool 50 includes an acting portion compressed from the surface SF of a brittle substrate 4 to inside for scribing the surface SF. Besides, the scribing tool 50 includes a shank 52, and a diamond grain 51 having the acting portion installed to the shank 52. In the acting portion, an apex PP and an edge line PS extending from the apex PP are provided. The diamond grain 51 includes a top surface SD0, and a set of sides SD1 and SD2 forming an edge line PS and the apex PP together with the top surface SD0. Each of a set of sides SD1 and SD2 has a surface roughness of Ra 0.04 μm or less in the acting portion.SELECTED DRAWING: Figure 1 |
