| 摘要 |
PURPOSE:To provide abrasive grains for grinding wheels suitable for high quality and high-efficient processing. CONSTITUTION:The abrasive grains comprises polycrystalline cubic baron nitride having over 1.7 average value and 0.4 or less standard deviation of the shape factor which is defined as the reciprocal of the ratio of the two-dimensional projection image of the grain to the circumcircle of the image. |
