摘要
氮和氢元素是天然及人工合成金刚石中重要的杂质元素,对金刚石的性能有着十分重要的影响。本工作中,先利用有机氮氢化合物三聚氰胺的分解提供氮与氢源,研究了大量的氮和氢在粉末触媒合成金刚石中对金刚石生长的影响。结果表明:大量的氮和氢的存在,将严重抑制金刚石的成核。然而,用含少量的添加剂氮化物Mx N的粉末触媒在国产六面顶压机上却能合成出优质金刚石单晶。利用光学显微镜观察,发现所合成的金刚石多为六八面体,晶形完整;在大多数用含添加剂氮化物的触媒合成的金刚石的晶面上有凹线出现。用扫描电镜对凹线的形貌进行了细致的观察。随着铁基粉末触媒中添加剂氮化物含量的增加,合成金刚石的压力和温度条件逐渐增高,金刚石生长的“V形区”
It is well known that the elements of nitrogen and hydrogen are the main impurities in natural and synthetic diamond and can affect the physical properties of diamonds.In this paper,the effects of nitrogen and hydrogen,which were from the melamine (C 3N 6H 6) decomposed,on diamond synthesized by HPHT were investigated.The results obtained in our study indicate that the nucleation of diamond was destroyed and the graphite/diamond conversion can be completely restrained by the abundant elements N and H in diamond synthesis by HPHT.However,high quality diamond crystals could be synthesized using a little M xN-added powder catalyst in cubicpress.The synthesized diamond crystals are observed to present integrated cubo-octahedral shape by optical microscopy.There are some accidented lines on the faces of the most diamond crystals,which are synthesized with M xN-added powder catalyst.We also observe the accidented lines under scanning electron microscope (SEM).When the content of M xN increases,the crystals growth conditions (the temperature and the pressure) increase and V-shapes section of the diamond growth moves upwards.
出处
《超硬材料工程》
CAS
2005年第1期6-10,共5页
Superhard Material Engineering
基金
国家自然科学基金项目 (5 0 172 0 18)
河南理工大学引进人才基金项目
