摘要
以SiC颗粒、MgAl2O4细粉为主要原料,分别外加质量分数为0、1%、2%、3%的稀土Y2O3,制备了SiC-MgAl2O4复合材料,在埋碳气氛下分别于1400、1500、1550、1600和1650℃保温5 h烧成。研究了Y2O3的添加量和烧成温度对SiC-MgAl2O4复合材料性能的影响,并通过XRD、SEM等手段对其物相组成和显微结构进行表征。结果表明:不同添加量的Y2O3均有利于碳化硅与尖晶石的烧结致密化。引入的Y2O3与MgAl2O4反应生成Y 3Al 5O 12,且其生成量随Y2O3添加量增加而增加。当烧成温度在1400~1600℃时,烧后试样致密化程度、力学强度随着烧成温度的增加而提高;当烧成温度高于1600℃时,烧后试样致密化程度、力学强度均下降。经1600℃烧结5 h后,外加Y2O3为2%(w),所制备的试样综合性能较优异,体积密度为2.78 g·cm-3,显气孔率为16.1%,高温抗折强度为3.98 MPa,常温抗折强度和弹性模量分别为14.5 MPa和57.7 GPa。
SiC-MgAl2O4 composite materials were prepared using SiC particles and MgAl2O4 fine powder as the main raw materials,extra adding Y2O3 with mass fraction of 0,1%,2%and 3%,respectively,firing at 1400,1500,1550,1600,and 1650℃under carbon embedded atmosphere for 5 h.The effects of the Y2O3 addition and the firing temperature on the properties of the SiC-MgAl2O4 composites were investigated.The phase composition and the microstructure of the specimens were characterized by XRD and SEM.The results indicate that different additions of Y2O3 are beneficial to the sintering densification of SiC-MgAl2O4.The introduced Y2O3 reacts with MgAl2O4 to produce Y 3Al 5O 12,and the yield increases with the rising Y2O3 addition.When the firing temperature is between 1400℃and 1600℃,the densification degree and the mechanical strength of the specimens increase with the rising firing temperature.When the firing temperature is higher than 1600℃,the densification degree and mechanical strength of the specimens decrease.The specimen with 2%Y2O3 sintered at 1600℃for 5 h possesses the optimal properties:the bulk density of 2.78 g·cm-3,the apparent porosity of 16.1%,the hot modulus of rupture of 3.98 MPa,the cold modulus of rupture of 14.5 MPa and the elastic modulus of 57.7 GPa.
作者
夏淼
孙红刚
李红霞
司瑶晨
杜一昊
尚心莲
Xia Miao;Sun Honggang;Li Hongxia;Si Yaochen;Du Yihao;Shang Xinlian(State Key Laboretore ot Advanced Refrectorics,Sinosteel Luoyang Institute ot Refrectorics Research Co.,Ltd.,Luoyang 441239,Henan,China)
出处
《耐火材料》
CAS
北大核心
2020年第5期374-379,共6页
Refractories
基金
NSFC-河南联合基金资助项目(U1604252)。
作者简介
夏淼:男,1994年生,硕士研究生。E-mail:xiamiao1306@foxmail.com;通信作者:李红霞,女,1965年生,博士,教授级高级工程师。E-mail:lihongx0622@l26.com。
