采用六方氮化硼合成Ⅱb型金刚石单晶的试验研究

Study on synthesizing Ⅱb type diamond single crystal with hexahedral nitride boron

在铁基触媒原材料中添加不同含量的六方氮化硼,采用粉末冶金方法制备片状触媒,在六面顶压机上进行金刚石合成试验。通过对比主要的合成参数发现,掺杂适量的六方氮化硼能够提高触媒的电阻,虽然对金刚石的成核有一定的抑制作用,但是有利于降低合成功率,同时有利于金刚石的粒度增粗。对合成出的金刚石的性能检测发现,适量的六方氮化硼掺杂有利于净化金刚石晶体,减少杂质与包裹体的数量,有利于降低磁化率,提高晶体的静压强度和冲击韧性。

The synthesizing diamond experiment is carried out at cubic hinge press apparatus with iron-based catalyst made by powder metallurgy,in which the hexahedral nitride boron(h-BN) is doped with different proportion.By comparing the main synthesizing parameters,it can be found that the resistance of catalyst increases due to doping of h-BN and this will restrain the diamond nucleation,while it will be useful for reducing the synthesizing power and coarsening the diamond grain size.The properties of diamond are tested.The results indicate that doping h-BN in catalyst with proper quantity can purify the diamond crystal by reducing the amount of impurity and inclusions.It is helpful to depress the magnetization rate and improve the static compressive strength and impact toughness.