径向温度导热材料对高温高压合成宝石级金刚石的影响

Influence of radial temperature-conducting materials on the synthesis of gem-grade diamonds at high-temperature and high-pressure

利用高温高压法合成宝石级金刚石时,其内部的径向温度场对其晶体粒度和晶体净度有重要影响。在常规合成结构基础上,选用不同径向温度导热材料以调节径向温度场进行高温高压宝石级金刚石的合成,研究了不同径向温度导热材料做为径向温度场调节材料时对晶体粒度和晶体净度的影响。结果表明,以高纯石墨片做为径向温度导热材料时,径向温度场平衡打破,为调节促进作用;以金属铁片做为径向温度导热材料时,径向温度场平衡同样打破,但为调节抑制作用。当高纯石墨片厚度为2.00mm时,其径向温度场的调节促进作用最为明显,合成的晶体粒度差异值在0.50ct以内,晶体净度A料占比达71.31%。

When gem-grade diamonds are synthesized by the high-temperature and highpressure method,the internal radial temperature field has an important influence on the crystal size and crystal purity.On the basis of the conventional synthesis structure,different radial temperature-conducting materials were used to regulate the radial temperature field for the synthesis of high-temperature and high-pressure gem-grade diamonds,and the effects of different radial temperature-conducting materials on the grain size and crystal purity were investigated as radial temperature-regulating materials.The results showed that when high purity graphite flake was used as the radial temperature conductive material,the equilibrium of the radial temperature field was broken,which was the promotion of regulation;when metal iron flake was used as the radial temperature conductive material,the equilibrium of the radial temperature field was broken as well,but it was the inhibition of regulation.When the thickness of the high-purity graphite sheet was 2.00 mm,the regulation and promotion of the radial temperature field was the most obvious,and the synthesized crystal size difference value was within 0.50 ct,and the ratio of the crystal purity A material reached 71.31%.