Structure of nanocrystalline WC-10%Co powder

作     者：杨志民 毛昌辉 杜军 Michel Daniel Champion Yannick Hagège Serge Htch Martin 

作者机构：General Research Institute for Nonferrous Metals Centre d'Etudes de Chimie Métallurgique/CNRS 94407 Vitry-sur-Seine France 

出 版 物：《中国有色金属学会会刊：英文版》 (Transactions of Nonferrous Metals Society of China)

年 卷 期：2001年第11卷第4期

页      面：529-534页

核心收录：

学科分类：0806[工学-冶金工程] 08[工学] 0818[工学-地质资源与地质工程] 0815[工学-水利工程] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0813[工学-建筑学] 0703[理学-化学] 0814[工学-土木工程] 0702[理学-物理学] 

基　　金：Project(PRAMX96-03)supportedbytheSinoFrenchAdvancedResearchProgram 

主　　题：structural properties mechanical milling WC Co 

摘      要：Nanostructured WC Co powders obtained by mechanical milling were investigated by combination of X ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM) techniques. Rietveld analysis indicates that the experimental XRD patterns cannot be satisfactorily explained with the hexagonal WC structure. HRTEM image analysis shows that in the as milled nanostructured powder, many WC grains contain stacking faults lying on the plane {10·0}. Analysis of phase images show that these defects are nearly periodically ordered along the direction. Based on these observations, a structural model was proposed for the WC grains with ordered stacking faults, which is in fact equivalent to a superstructure of WC with space group Amm2. When this model describing the faulted fraction of WC is introduced together with the normal WC structure (space group P6-m2) into the Rietveld refinement, a much better agreement between the calculated and experimental XRD profiles was obtained. This study allows to obtain the lattice parameters, grain size, microstrain and other structural information on the as milled powders.