| 摘要 |
A peripheral grinding wheel wherein the peripheral grinding portion contains diamond or cubic boron nitride abrasive particles and is characterised in that it consists of two co-axial sections, the one section being a coarse section and containing coarse particles of between 60/80 mesh and 100/120 mesh and the other being a fine section containing fine particles of between 170/200 and 300/350 mesh, or in that it consists of a fine section sandwiched between two coarse sections, in each case the concentration of abrasive particle in the fine section preferably being greater than the concentration of abrasive particle in the coarse section. |
