包裹体作用下的人造金刚石单晶的破裂  

Fracture of synthetic diamond monocrystal induced by inclusions

作　　者：李和胜[1] 亓永新[1] 李木森[1] 

机构地区：[1]山东大学材料科学与工程学院

出　　处：《超硬材料工程》2008年第3期1-4,共4页Superhard Material Engineering

基　　金：国家自然科学基金(No.50772060);山东省自然科学基金(No.Y2007F12);山东省博士后创新项目专项基金(No.200702024)

摘　　要：使用Diashape形貌分析系统,通过分析晶体的透光性和纯净度对人造金刚石所含包裹体的情况进行分级。选取包裹体含量中等的金刚石晶体,一部分在静压强度仪上施压致其开裂;另一部分通过高温煅烧致其开裂。使用超声波将已开裂晶体震开,通过分析断面形貌和成分,分析包裹体致金刚石晶体破裂失效的原因。试验发现,无论是受压,还是受热,金刚石的开裂面均平行于(111)晶面。包裹体与晶体的界面是应力集中的位置,也是裂纹源。晶体受压开裂是由于包裹体与晶体的弹性模量不同;而晶体受热之后的破裂失效,则是由于膨胀系数的不同所致。In this paper, the synthetic diamond single crystal was classified by its content of inclusions on basis of the transparency and purity of crystal detected by Diashape analysis system. Some medium crystals were pressed to dehiscence with the testing equipment of static compressive strength and others were heated and oxidized to dehiscence. Then, the cracked crystals were shattered by supersonic wave with the aim to study the reason for fracture of synthetic diamond crystal induced by inclusions. The experimental results indicate that the fracture section is parallel to the （111） plane of diamond crystal in the two situations. The interface between the inclusions and the crystal is the position where the stress concentrated as well as the source of cracks. When the crystal was pressed, the reason for fracture is the difference of the elastic ratio between the inclusions and the crystal. While be heated, the reason is the difference of expansion coefficient.

关 键 词：人造金刚石 包裹体 破裂 高温高压 

分 类 号：TQ164[化学工程—高温制品工业]