中文摘要：

Fe-C（H）系高温高压金刚石多晶在合成片上呈成堆聚集状、不均匀分布。多晶中的金刚石晶粒多为八面体晶形、随机定向、大小无规律,表面发育＂锯齿状＂生长台阶,普遍发育塑性形变等缺陷。多晶中的金刚石晶粒间接触界线清晰、呈突变状。无论是利用晶体成核、还是晶体长大理论都只能解释多晶中存在的部分现象。利用碳原子配位四面体生长基元模型分析多晶的形成机制值得探索。深入分析Fe-C（H）系高温高压合成金刚石多晶的形成机制不但有利于改善金刚石合成的工艺、提高合成金刚石多晶的品级,而且有利于为人们探讨天然金刚石多晶的形成机制及其深部意义提供科学线索。

英文摘要：

The HPHT synthetic polycrystalline diamonds form Fe-C（H）system have an unevenly clustered distribution on the disk.Diamond grains randomly oriented in Polycrystalline have octahedral habit and different sizes.Also,there are Zigzag stripes on the gain surfaces and widespread development of plastic deformation and other defects in the diamond grains.The diamond grain boundaries are clear and solid contact mutant.Based on the crystal nucleation and crystal growth theory,only parts of experimental results of the polycrystalline can be explained.The usage of carbon atom coordination tetrahedron growth units model in explaining the formation mechanism of the polycrystalline entails further studying.The In-depth analysis of the formation mechanism of the high pressure-high temperature synthetic polycrystalline diamond from Fe-C（H）system will not only optimize diamond synthesis craft and improve the grade of the polycrystalline diamond,but also provide scientific clues for the formation mechanisms of natural polycrystalline diamond.