Effects of aluminum additive on diamond crystallization in the Fe-Ni-C system under high temperature and high pressure conditions  

作　　者：ZHANG ZhuangFei JIA XiaoPeng LIU XiaoBing HU MeiHua LI Yong YAN BingMin MA HongAn 

机构地区：[1]State Key Laboratory of Superhard Materials,Jilin University,Changchun 130012,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2012年第5期781-785,共5页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the New Century Excellent Talents in University and the National Natural Science Foundation of China (Grant Nos.50572032,50731006 and 50801030)

摘　　要：In this paper, we investigate diamond crystallization in Fe-Ni-C with an aluminum additive and the capability of aluminum for converting graphite to diamond in a series of experiments at 4.9-5.5 GPa and 1240-1500℃. Our experimental results show that the growth habits of diamond crystal have been significantly influenced by the addition of aluminum as a catalyst. The crystal color changes from yellow to nearly colorless. The morphology of the synthesized diamond crystals gradually changes from cubic-octahedron to octahedron in the Fe-Ni-C systems with increasing aluminum additive. The lowest synthesis conditions fell first and then rose with increasing aluminum. We found a suitable addition of aluminum is very effective in lowering the synthesis conditions while an excessive aluminum additive may have a suppressive effect on the diamond nucleation.In this paper,we investigate diamond crystallization in Fe-Ni-C with an aluminum additive and the capability of aluminum for converting graphite to diamond in a series of experiments at 4.9-5.5 GPa and 1240-1500°C.Our experimental results show that the growth habits of diamond crystal have been significantly influenced by the addition of aluminum as a catalyst.The crystal color changes from yellow to nearly colorless.The morphology of the synthesized diamond crystals gradually changes from cubic-octahedron to octahedron in the Fe-Ni-C systems with increasing aluminum additive.The lowest synthesis conditions fell first and then rose with increasing aluminum.We found a suitable addition of aluminum is very effective in lowering the synthesis conditions while an excessive aluminum additive may have a suppressive effect on the diamond nucleation.

关 键 词：crystal morphology DIAMOND aluminum additive 

分 类 号：O722.4[理学—晶体学] TN304.18[电子电信—物理电子学]