FeWB基陶瓷在真空烧结过程中的组织演变和相转变（英文）  

Microstructure Evolution and Phase Transformation of FeWB Based Cermets During the Vacuum Sintering

作　　者：余虹位 李军[1,2] 李程[1] 刘颖[1,2] 

机构地区：[1]四川大学,四川成都610065 [2]先进特种材料与技术教育部重点实验室,四川成都610065

出　　处：《稀有金属材料与工程》2018年第2期463-468,共6页Rare Metal Materials and Engineering

摘　　要：研究了烧结温度和保温时间对反应硼化烧结制备FeWB基陶瓷的影响。利用X射线衍射,扫描电镜和能谱仪对FeWB基陶瓷烧结过程中的相转变,微观组织以及反应机理进行了表征。结果表明,FeWB硬质相是通过W+Fe_2B=FeWB+Fe和Fe B+W=FeWB两种方式合成的,并且反应生成的FeWB晶粒呈等轴形貌。在800~1150℃之间,FeWB基陶瓷的密度骤然升高,这与Fe_2B相的熔化有关。在1300℃时,由于W2B相的存在,会使FeWB相转变为Fe_7W_6相,从而使密度进一步升高。随着烧结温度的提高,通过液相烧结制备的金属陶瓷表现出相对均匀的微观结构,而且原位合成的FeWB颗粒会发生长大。为了获得较高的致密度,FeWB基陶瓷的烧结温度应控制在1150~1250℃之间。其次,适当的增加铁和硼铁的含量有利于烧结的致密化。The FeWB based cermets were produced by the reaction boronizing sintering at different temperatures and with different holding time. The influences of temperature and holding time on the phase transformation, microstructure of cermets as well as the reaction mechanism were investigated by X-ray diffraction meter（XRD）, scanning electron microscopy（SEM） and energy disperse spectroscopy（EDS）. The results show that the hard phase FeWB is produced in the compact at the stage of solid phase sintering by the reaction W＋Fe2B=FeWB＋Fe and W＋FeB =FeWB. Besides, the FeWB phase exhibits an equiaxed morphology. The distinctly rapid densification occurs at the temperature ranging from 800 to 1150 ℃. When the temperature exceeds 1300 ℃, the FeWB phase transforms to Fe7W6 phase, which results in the further improvement of the density. With the increase of temperature, the cermets prepared by liquid phase sintering exhibit a relatively homogenous microstructure, accompanied by in situ growth of thick FeWB grains. In order to obtain a higher density, the sintering temperature of preparing FeWB based cermets should be controlled between 1150 and 1250 ℃. Moreover, it is necessary to appropriately increase the content of iron and ferro-boron.

关 键 词：FeWB基陶瓷 反应硼化烧结 相转变 致密化 

分 类 号：TQ174.1[化学工程—陶瓷工业]