多次冲击石墨合成聚晶金刚石的实验研究

 利用高能炸药爆轰产物驱动金属飞片，碰撞“硬”回收包套以输入平面冲击波，在24~37 GPa的压力范围内，对纯石墨进行1~4次的冲击压缩实验，合成出了纯度很高、形貌良好的立方型聚晶金刚石。随着冲击次数的增加，金刚石的转化率和粒度有增大的趋势。但是，当金刚石粒度较大时（约100 μm以上），如果冲击温度较低（约1 000 K以下），同时冲击压力又较高（约20 GPa以上），金刚石颗粒就容易被冲击波破碎。

EXPERIMENTAL STUDY ON THE POLYCRYSTAL DIAMOND SYNTHESIS FROM GRAPHITE BY MULTIPLE SHOCK-COMPRESSIONS

Pure graphite powders were subjected to single to fourfold shock-compressions by use of an explosively driven metal flyer impacting onto the recovery capsule, and polycrystal cubic diamond of high purity and with regular morphology was synthesized from the graphite under pressures from 24 to 37 GPa. Conversion ratio from graphite and particle size of diamond displayed an increased trend with the compression times. When the particle size of diamond is greater than about 100 μm, however, it is easily to be fractured if the shock pressure is high (over 20 GPa) while the temperature is low (below 1 000 K).