Microstructures of surface layer (near diamond) of the metallic film from Fe Ni C system are composed of (Fe,Ni) 3C, (Fe,Ni) 23 C 6 and γ (Fe,Ni), from which it can be assumed that graphite isnt directly catalyzed ...Microstructures of surface layer (near diamond) of the metallic film from Fe Ni C system are composed of (Fe,Ni) 3C, (Fe,Ni) 23 C 6 and γ (Fe,Ni), from which it can be assumed that graphite isnt directly catalyzed into diamond through the film and there exists a transition phase (Fe,Ni) 3C that can decompose into diamond structure. AFM morphologies on the film/diamond interface are traces preserved after carbon groups moving from the film to diamond. The morphologies on the as grown diamond are similar to those on corresponding films, being spherical on (100) face and sawtooth like steps on (111) face. Diamond growth rates and temperature gradients in boundary layer of the molten film at HPHT result in morphology differences.展开更多
Diamond single crystals grown from Fe-Ni-C system at high temperature-high pressure (HPHT) usually contain inclusions related to the metallic catalyst. During the diamond growth, the metallic inclusions are trapped by...Diamond single crystals grown from Fe-Ni-C system at high temperature-high pressure (HPHT) usually contain inclusions related to the metallic catalyst. During the diamond growth, the metallic inclusions are trapped by the growth front or are formed through reaction between the contaminants trapped in the diamond. In the present paper, the metallic inclusions related to the catalyst were systematically examined by transmission electron microscopy (TEM). The chemical composition and crystal structure of the metallic inclusions were for the first time determined by selected area electron diffraction pattern (SADP) combined with energy dispersive X-ray spectrometry (EDS). It is shown that the inclusions are mainly composed of orthorhombic FeSi2, fcc (FeNi)23C6, and orthorhombic Fe3C, hexagonal Ni3C.展开更多
文摘Microstructures of surface layer (near diamond) of the metallic film from Fe Ni C system are composed of (Fe,Ni) 3C, (Fe,Ni) 23 C 6 and γ (Fe,Ni), from which it can be assumed that graphite isnt directly catalyzed into diamond through the film and there exists a transition phase (Fe,Ni) 3C that can decompose into diamond structure. AFM morphologies on the film/diamond interface are traces preserved after carbon groups moving from the film to diamond. The morphologies on the as grown diamond are similar to those on corresponding films, being spherical on (100) face and sawtooth like steps on (111) face. Diamond growth rates and temperature gradients in boundary layer of the molten film at HPHT result in morphology differences.
文摘Diamond single crystals grown from Fe-Ni-C system at high temperature-high pressure (HPHT) usually contain inclusions related to the metallic catalyst. During the diamond growth, the metallic inclusions are trapped by the growth front or are formed through reaction between the contaminants trapped in the diamond. In the present paper, the metallic inclusions related to the catalyst were systematically examined by transmission electron microscopy (TEM). The chemical composition and crystal structure of the metallic inclusions were for the first time determined by selected area electron diffraction pattern (SADP) combined with energy dispersive X-ray spectrometry (EDS). It is shown that the inclusions are mainly composed of orthorhombic FeSi2, fcc (FeNi)23C6, and orthorhombic Fe3C, hexagonal Ni3C.
