水雾化粉末状触媒中固溶碳对金刚石合成的影响初探  

Discussion on the effect of carbon solution in water-atomized powder catalyst on diamond synthesis process

作　　者：徐燕军[1] 尹翔[2] 

机构地区：[1]北京钢铁研究总院,北京100020 [2]安泰科技股份公司,北京100020

出　　处：《金刚石与磨料磨具工程》2008年第2期41-45,共5页Diamond & Abrasives Engineering

摘　　要：高压水雾化方法制备触媒粉末为降低粉末氧含量,实验中加入合成金刚石用高纯天然鳞片石墨粉,灰分含量小于20×10-6,制备成合成柱在六面顶压机上进行系列合成实验,合成腔体为41 mm,通过合成的金刚石结果,判断总结出最佳含碳量值。所制得FeNi30触媒粉末中的碳有两种状态存在:固溶单质碳和Fe3C型碳化物。结果发现固溶单质碳的存在,促进碳在触媒合金中内外双向扩散,促进了金刚石成核和转化;另外,根据固体与分子经验电子理论,分别计算了Fe3C及(Fe,Ni)3C型碳化物内C-C键原子组成的晶面的共价电子密度与金刚石晶面的共价电子密度,发现二者之间具有连续性,说明Fe3C型碳的存在也很有可能是金刚石形核与生长的有效碳源。During the preparation of catalyst powder by high -pressure water atomizing, in order to lower oxygen content, highly pure flake graphite powder was used in the experiment, with the ash content less than 20 × 10^-6. Series of experiments were conducted on cubic press to synthesize diamond, the synthesize chamber was 641 mm. Synthesis experiment results were observed and compared in order to find out the optimal carbon content in the catalyst. The carbon powder in FeNi30 catalyst may exist in two states： single - solution of carbon and Fe3 C carbide. The results showed that the existence of single solution of carbon promoted the diffusion of carbon to both internal and external in the catalyst alloy and accelerated the nucleation and transformation of the diamond. Furthermore, in accordance with solid and molecular experience in the electronic theory, we calculated the valence electron density of crystal surface and diamond surface composed by C -C bond atoms in Fe3C and （Fe, Ni） 3C carbide, and found out that there was continuity between them, which means that the presence of Fe3 C is very likely to be the effective carbon resource for diamond nucleation and growth .

关 键 词：粉末触媒 金刚石 固溶碳 高压水雾化 

分 类 号：TQ164[化学工程—高温制品工业]