利用自行设计与集成的二级6—8型大腔体静高压装置,研究了影响八面体压腔高压发生效率的主要因素及机理,并提出了一种八面体压腔密封的简化力学模型.针对于10/4(八面体传压介质边长为10mm,二级WC立方体增压块截角边长为4mm)组装的实验结果发现:预密封边尺寸会显著影响八面体压腔的压力产生效率;在腔体压力为12GPa左右时,高压发生效率随八面体MgO传压介质初始密度的增加而提高;在15GPa以上时,影响压力产生效率的主要因素是WC增压立方块本身的强度以及加压过程中所形成密封边的尺寸及材料.
In the present study,we investigated the major factors and mechanisms of the pressure generation efficiency of the two-stage multianvils high pressure apparatus,which was recently designed and assembled in our laboratory. A simplified mechanical model of the pressure cell assembly was also proposed to interprete the experimental data. The results with the 10 /4 (with octahedral edge-length of 10 mm,and WC cube truncation edge-length of 4 mm) cell assembly indicate that the pressure efficiency is very sensitive to the gaskets size and can be improved with the increased initial density of MgO pressure transmitting medium when cell pressure is about 12 GPa. Above 15 GPa,the pressure efficiency is mainly limited by the yield strength of the second stage WC cubes,as well as the composition and size of gaskets.