| 摘要 |
A super hard polycrystalline construction, suitable for abrasive applications comprising a body of polycrystalline super hard material (PCD). This material comprises a first fraction of super hard grains and a second fraction of super hard grains, where the first fraction has a greater average grain size than the super hard grains in the second fraction. The super hard grains in the first and second fraction have a peripheral surface where the super hard grains in the first fraction are bonded along at least a portion of the peripheral surface to at least a portion of a plurality of super hard grains in the second fraction. The super hard grains in the first fraction are spaced from adjacent grains in the first fraction by a distance of between 50-500nm. This is made by HPHT treatment of an at least bimodal starting powder of preferably diamond having one fraction with a particle size of 50-500 nm. |
