Si3N4结合SiC耐火材料的高温重烧结研究  

High-temperature post-sintering of silicon nitride bonded silicon carbide refractories

作　　者：刘臻[1] 吴吉光[1] 王佳平[1] 梁鹏鹏 石会营[1] Liu Zhen;Wu Jiguang;Wang Jiaping;Liang Pengpeng;Shi Huiying(Sinosteel Luoyang Institute of Refractories Research Co,Ltd.,State Key Laboratory of Advanced Refractories,Luoyang 471039,China)

机构地区：[1]中钢集团洛阳耐火材料研究院有限公司先进耐火材料国家重点实验室,洛阳471039

出　　处：《耐火与石灰》2020年第4期7-10,15,共5页Refractories & Lime

摘　　要：以Si粉、SiC颗粒和细粉为原料,通过反应烧结(最高烧成温度1 420℃)制备Si_3N_4结合SiC标型砖,再将标型砖在流动N2气氛、1 750℃烧结2. 5 h,制得重烧结Si_3N_4结合SiC耐火材料。利用XRD、EDS、SEM和压汞法对重烧结前后的Si_3N_4结合SiC试样的化学组成、微区组成、微观结构以及孔径分布等性能进行检测,其结果表明:Si_3N_4结合SiC耐火材料高温重烧结后,外形基本没有变化,材料体积密度少量降低,常温抗折强度和1 400℃抗折强度少量提高,试样中纤维状Si_3N_4消失,α-Si_3N_4全部转变为较大尺寸的柱状β-Si_3N_4;试样平均孔径显著增加;试样抗高温水蒸汽氧化性能显著提高。Based on Si powder,SiC grains and powder as the raw materials,Si3N4-bonded SiC standard bricks were prepared by reactive sintering(at maximum 1420℃)through the same processes,which were then post-sintered at 1750℃for 2.5 hours in flowing N2 atmosphere.The phase compositions,micro-zone compositions,microstructure as well as pore-size distribution of Si3N4-bonded SiC samples before and after post-sintering were analyzed by means of XRD,EDS,SEM and mercury intrusion method respectively.The results showed that after post-sintering at high temperature,the Si3N4-bonded SiC refractories,in which fibrous Si3N4 disappeared and allα-Si3N4 were transformed to relatively large-sized columnarβ-Si3N4,presented almost no dimensional change,only a little decrease of bulk density and a little increase of MOR and HMOR(1400℃);the average pore-size increased dramatically;the steam oxidation resistance at high temperature was also enhanced remarkably.

关 键 词：Si3N4结合SiC耐火材料 重烧结 抗水蒸汽氧化 孔径分布 

分 类 号：TQ175.12[化学工程—硅酸盐工业]