添加硅和硅微粉氧化铝–碳纳米管耐火材料的制备与性能  

Effects of Silicon and Microsilica Additive on Microstructure and Mechanical Properties of Al_2O_3–C Multi-walled Carbon Nanotubes Refractories

作　　者：廖宁[1] 李亚伟[1] 桑绍柏[1] 

机构地区：[1]武汉科技大学、省部共建耐火材料与冶金国家重点实验室,武汉430081

出　　处：《硅酸盐学报》2017年第3期433-440,共8页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(51372176,51574186)资助

摘　　要：研究了铝碳耐火材料中多壁碳纳米管(MWCNTs)在添加硅和硅微粉条件下的结构演变以及添加单质硅、硅和硅微粉对材料性能的影响。结果表明:高温下材料内单质硅与二氧化硅反应,导致大量的SiO(g)形成,加快了800℃以上MWCNTs的结构演变进程,促进MWCNTs蚀变为SiC晶须。正是由于SiC晶须形成,添加硅和硅微粉铝碳耐火材料经1 400℃处理后的抗折强度达到22.56 MPa,而单独添加单质硅的试样仅为19.24 MPa。然而,对于材料的抗热震性来说,未添加硅微粉的试样热震后强度保持率为43.51%,明显高于硅微粉试样的28.65%,这主要是由MWCNTs有助于提高材料的韧性,而Si C晶须主要起到增强的作用。The structure evolution of multi-walled carbon nanotubes （MWCNTs） in A12O3-C matrix with silicon and microsilica additives was investigated. The influences of silicon/microsilica additives as well as silicon additive on the properties of A12O3-C refractories were analyzed. The results show that a greater content of SiO vapor is formed through the reaction of silicon and microsilica, which stimulates the structure evolution of MWCNTs and facilitates the formation of SiC whiskers at 〉 800 ℃. With the formation of large amount of SiC whiskers, the CMOR of A12O3-C refractories with silicon and microsilica reaches 22.56 MPa, which is greater than that of refractories with only silicon （i. e., 19.24 MPa）. However, the specimen without microsilica has a greater residual strength ratio （i.e., 43.51%）, compared to the specimen with microsilica （i.e., 28.65%）. It is indicated that the MWCNTs are more beneficial to toughening, and SiC whiskers are responsible for strengthening.

关 键 词：铝碳耐火材料 显微结构 力学性能 硅微粉 多壁碳纳米管 

分 类 号：TQ175[化学工程—硅酸盐工业]