添加稀土对FeNi30粉末触媒合成金刚石的影响

Effects of adding rare earths on synthesizing diamond with FeNi30 powder catalyst

在FeNi30合金中添加稀土，利用气雾化技术制备稀土含量分别为B％、C％和D％的FeNi30＋Re触媒粉末，并进行金刚石合成实验，研究稀土对FeNi30＋Re粉末触媒合成金刚石的影响。结果表明，FeNi30合金中添加稀土能降低粉末触媒中的氧含量，金刚石混合单产从98．2提高到104．4ct／块，粗颗粒比例、静压强度和冲击韧性都有所提高，并能降低磁化率；金刚石颜色从浅黄绿色变为深黄绿色。其中以稀土添加量为C％时合成效果最佳。此外，还利用化学反应热力学理论对添加稀土降低触媒粉末中的结合氧和提高触媒粉末的催化活性机理进行了分析。

Three kinds of FeNi30 ＋ Re catalyst powders with rare earth contents （mass fraction） of B%, C% and D% respectively were prepared and used to carry out synthesizing diamond＇s tests. The effects of rare earth on synthesizing diamond were also investigated. The results indicate that the addition of rare earths is useful to reduce the oxygen content of powder catalyst, improve the diamond＇s mixing yield from 98.2 to 104.4 carat per block, increase the proportion of coarse particles, static strength and impact toughness values, decrease the diamond＇s magnetic susceptibility, and change the diamond＇s color from shallow yellow green to deep yellow green. The results have proved that the rare earths content of C% is the best. Besides, the theory of thermodynamics of chemical reactions has also been used to analyze the mechanism of rare earth in reducing oxygen content and improving the catalytic activity of the catalyst powder.