| 摘要 |
A fracture resistant wearing edge is provided on unicrystalline alpha alumina material by the intersection of planar surfaces which are parallel to m-planes of the unicrystalline alpha alumina. Such planar surfaces intersect at an angle of 60 DEG or 120 DEG and the intersection of such surfaces is an edge substantially parallel to the C-axis of the unicrystalline alpha alumina material. |
