| 摘要 |
<p>A cutting structure, for a rotary drill bit, is of the kind comprising a preform cutting element 18 having a front cutting face formed of superhard material, such as polycrystalline diamond, 20 and a rear face bonded to a carrier 19 of less hard material, such as cemented tungsten carbide. The cutting element is bonded to the carrier by means of an ally having the following composition: Ni 30 - 60% Pd 30 - 62% Si 3 - 15% An alternative alloy has the following composition: Cr 4 - 10% Fe 1 - 5% Si 2 - 7% C 0.01 - 0.10% B 2 - 5% Ni Balance ompri</p> |
