Tailoring the Mechanical Properties of Al2O3-C Refractories by Controlling MWCNTs Evolution
B4C and microsilica were adopted to tailor the transformation of MWCNTs in Si containing Al2O3-C refractories.The corresponding phase compositions and microstructures of Al2O3-C refractories were investigated by means of X-ray diffraction (XRD), (SEM)and scanning electron microscopy, respectively.The mechanical properties and thermal shock resistance were investigated through three-point bending test and water quenching method.The results show that B4C prevented the structure transformation of MWCNTs at 1000 ℃ and suspended the transformation at 1200 ℃ attributes to the decreased O2 partial pressure.In contrast, the reaction between SiO2 and Si increased the SiO partial pressure, which stimulated the transformation of MWCNTs into SiC whiskers.Abundant SiC whiskers formed in SiO2 containing system improved the mechanical properties while the thermal shock resistance declined.In comparison, more residual MWCNTs and newly formed MWCNTs in B4C containing Al2O3-C refractories contributed to improve thermal shock resistance owing to toughening effects of MWCNTs.
microsilica B4C MWCNTs transformation mechanical properties Al2O3-C refractories
LIAO Ning LI Yawei SANG Shaohai
The State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,China
国际会议
西安
英文
1-8
2016-09-20（万方平台首次上网日期，不代表论文的发表时间）