基于CASTEP的第一性原理方法,研究了六面顶压机高压腔体常用组装材料在30GPa以内的压力与晶胞参数关系,给出了超硬材料工程压力范围内(3~10GPa)的常用材料的布里奇曼状态方程.以0℃~1800℃、高压下氯化钠的压力-体积实测数据,进行了布里奇曼状态方程的拟合,讨论了状态方程在合成金刚石复合片条件下的有效性.利用材料的布里奇曼方程和高压腔体中组装材料的压缩率,进行组装材料的体积和结构的设计,在相同表压的条件下,实现了高压腔体内压力的明显提高.在六面顶压机上进行了合成了金刚石/硬质合金复合体试验,验证了这种设计方法的可靠性.%Based on the first-principles method of CASTEP,the relationship between pressure and the cell parameters of the common assembly materials for the high pressure cavity of cubic press within 30GPa has been studied,and the Bridgman equation of state of the common materials within the superhard material engineering pressure range (3~10GPa) has been provided.The Bridgman equation of state has been fitted based on the pressure-volume measured data of sodium chloride at 0℃~1800℃ under high pressure.And the effectiveness of the equation of state under the conditions of diamond compact synthesis has been discussed.The volume and structure of the assembly materials has been designed based on the the Bridgman equation of state of the materials and the compression ratio of the assembly materials within the high pressure cavity.The pressure inside the high pressure cavity has been significantly increased under the same gage pressure.The reliability of the design has been verified through experiment of diamond/ cemented carbide composite synthesis by cubic apparatus.
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