| 摘要 |
PROBLEM TO BE SOLVED: To provide a rough ceramic ball which prevents wear and flawing of a grindstone for polishing and can prevent occurrence of defects in the rough ceramic ball itself and to provide a method for manufacturing the rough ceramic ball. SOLUTION: The rough ceramic ball (1) has a beltlike part (5) having 4 mm width and 0.15 mm height h of both ends at the center of the surface of a spherical substrate (3) having 10 mm diameter (on the circumference having the maximum radius with respect to the central axis: on the equator) all over the substrate in the circumferential direction. The beltlike part (5) has edge parts (7) at both ends in the width direction (in the horizontal direction of figure 2). Each edge part (7) is rounded with a radius of 0.1 mm or more. |
