纳米碳化硅的高温高压稳定性研究  

Study on the Stability of Nanometer Silicon Carbon under High-Pressure and High-Temperature

作　　者：邓小清[1] 贺红亮[2] 唐敬友[3] 方家元[1] 

机构地区：[1]长沙理工大学物理与电子科学系,湖南长沙410076 [2]中国工程物理研究院,四川绵阳621900 [3]西南科技大学材料系,四川绵阳621002

出　　处：《长沙电力学院学报（自然科学版）》2006年第2期80-83,共4页JOurnal of Changsha University of electric Power:Natural Science

摘　　要：对纳米碳化硅的高温高压稳定性和分解行为进行了实验研究.通过对比实验,分别研究了:①纳米碳化硅在高温高压下的分解;②纳米S iC分别在纳米N i和N i70Mn25CO5合金片参与下的高温高压稳定性.实验观察到:高温有利于纳米S iC的分解;过渡金属的参与,将明显加快纳米S iC的分解;S iC分解后的终态产物存在形式与外部环境有密切关系,在本实验中,分解后的C主要转化为石墨,分解后的S i主要与O结合形成了柯石英(S iO2),或表现为非晶态形式.The stability and decomposition behavior of SiC nanometer powders was studied under the high pressure and high temperature. Three kind of experiments were conducted by using three different starting materials：①nanometer SiC only;②nanometer SiC mixed with nanometer Ni and nanometer SiC placed with Ni70Mn25Co5 alloy plates. Results are briefly summarized as follows： （a）. Decomposition of nanometer SiC is much easier than that of micrometer SiC. Decomposition of pure nanometer SiC has been observed to start at 1 250 ℃ and 5.8 GPa, however, for the micrometer SiC it could be higher than 2 000 ℃ at latm; （b）. An obvious promotion is occurred in decomposition of SiC with the help of Ni nanometer powder and Ni70Mn25CO5 alloy; and （c）. The decomposing products are sensitively dependent on the environment materials. In this study carbon from SiC is mainly transformed into graphite, but silicon partially to coesite（ SiO2） and to amorphous state, respectively. Formation of coesite is explained due to a great deal of oxygen absorbed on the nanometer powders, and resulted from the reaction of oxygen with silicon at high pressure and high temperature.

关 键 词：纳米碳化硅 触媒 分解 

分 类 号：O452[理学—无线电物理]