利用场发射扫描电子显微镜(FESEM)和X射线能谱仪(EDS)研究了高温高压触媒法合成金刚石后金刚石/触媒界面的物相组成,发现铁镍元素与碳元素的原子比为3.1: 1,并分析得出高温高压下界面中存在Fe3C、Ni3C物相结构.据此,利用热力学中经典的ΔG<0判定法,计算Me3C(Me:Fe,Ni)物相分解出金刚石的自由能变化.结果表明:在触媒法合成金刚石条件下(1500～1700 K、5～6 GPa),Me3CC(金刚石)+3Me比石墨金刚石的ΔG更负.因此,从热力学角度看,Me3C的形成,尤其是铁基触媒中Fe3C、Ni3C的形成,说明触媒法合成金刚石单晶是来自于Me3C型碳化物的分解,而并非石墨结构的直接转变.
参考文献
| [1] | Yin L W;Li M S;Gong Z G et al.A Relation between a Metallic Film Covering on Diamond Formed during Growth and Nanosized Inclusions in HPHT as-grown Diamond Single Crystals[J].Applied Physics A:Materials Science and Processing,2003,76:1061. |
| [2] | Xu B;Li MS;Cui JJ;Gong JH;Wang SH .An investigation of a thin metal film covering on HPHT as-grown diamond from Fe-Ni-C system[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2005(1/2):352-359. |
| [3] | 许斌,李木森,尹龙卫,崔建军.铁基触媒合成金刚石形成的金属包膜的组织结构[J].硅酸盐学报,2003(05):470-475. |
| [4] | 许斌,崔建军,王淑华,李木森,李成美,冯立明.人造金刚石单晶铁基金属包膜的精细结构[J].金属学报,2005(04):444-448. |
| [5] | Shatynski S R .The Thermochemistry of Transition Metal Carbides[J].Oxidation of Metals,1979,13(02):105. |
| [6] | Naka S;Tsuzuki A;Hirano S I .High Temperature and Pressure Preparation and Properties of Iron Carbides Fe7C3 and Fe3C[J].Materials Science,1984,19:259. |
| [7] | Putyatin A A;Makarova O V;Semenenko K N .Interaction in the Fe-C System at High Pressures and Temperature[J].Severkhtverdye Materialy,1989,11:3. |
| [8] | Perry J;Nelson S;Hosomi S .Diamond Formation in Solid Metal[J].Materials Research Bulletin,1990,25:749. |
| [9] | Hong S M;Li W;Jia X P .Diamond Formation from a System of SiC and a Metal[J].Diamond and Related Materials,1993,2:508. |
| [10] | Strong H M;Chrenko R M .Diamond Growth Rates and Physical Properties of Laboratory-made Diamond[J].Physical Chemistry,1971,75:1838. |
| [11] | Nishitani S R;Ishihara K N;Suzuki R O et al.Metastable Solid Solubility Limit of Carbon in the Ni-C System[J].Journal of Materials Science Letters,1985,4:872. |
| [12] | 许斌,李丽,田彬,范小红,冯立明.高温高压触媒法金刚石生长的热力学分析[J].高压物理学报,2009(03):189-195. |
| [13] | 叶大伦;胡建华.实用无机物热力学数据手册[M].北京:冶金工业出版社,2002 |
| [14] | Sung J J .Graphite'Diamond Transition under High Pressure:A Kinetics Approach[J].Materials Science,2000,35:6041. |
| [15] | Mounet N;Marzari N .High-accuracy First-principles Determination of the Structural,Vibrational and Thermodynamical Properties of Diamond,Graphite and Derivatives[J].Physical Review B:Condensed Matter,2005,71(20):205. |
| [16] | Francis B .Finite Elastic Strain of Cubic Crystals[J].Physical Review,1947,71(11):809. |
| [17] | Jang J H;Kim I G .First-principles Calculations and the Thermodynamics of Cementite[J].Materials Science Forum,2010,3319:638-642. |
| [18] | Michal M;Paul E;Karsten A .Analytic Bond-order Potential for BCC and FCC Iron-Comparison with Established Embedded-Atom Method Potentials[J].Journal of Physics:Condensed Matter,2007,19:326220. |
| [19] | Morgan W C .Thermal Expansion Coefficients of Graphite Crystals[J].Carbon,1972,10:73. |
| [20] | Reeber R R;Wang K .Thermal Expansion,Molar Volume and Specific Heat of Diamond from 0 to 3000K[J].Elect Mater,1996,25:63. |
| [21] | 刘志林;李志林.界面电子结构与界面性能[M].北京:科学出版社,2002 |
| [22] | 张瑞林.固体与分子经验电子理论[M].长春:吉林科学技术出版社,1993 |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%