Processing and Characterization of Multi-Walled Carbon Nanotubes Containing Alumina-Carbon Refractories Prepared by Nano
- PDF / 1,658,653 Bytes
- 8 Pages / 593.972 x 792 pts Page_size
- 4 Downloads / 182 Views
UCTION
REFRACTORIES containing carbon are important materials used in the iron and steel industry. In recent years, nanoscale additives have been included in refractories containing carbon to improve their properties. For example, Roungos and Aneziris[1] reported that the combination of nanoscale powders based on carbon nanotubes (CNTs) and alumina nanosheets led to refractories with superior thermal shock performance and approximately 30 pct less residual carbon in comparison to commercially available Al2O3-C refractories. Bag et al.[2] added nanoscale carbon black into MgO-C refractories to reduce the carbon content and found that the mechanical properties, thermal shock resistance, and slag corrosion resistance were improved. Liu et al.[3] studied the effects of nanometer carbon black on the mechanical properties of low-carbon MgO-C refractories and found that the modulus of rupture and crushing strength increased gradually with increasing nanoscale carbon black content. Matsuo et al.[4] reported that the mechanical strength of MgO-C refractories was remarkably improved by the addition of carbon nanofibers. Pagliosa et al.[5] developed a special nanographite FENG LIANG, Postdoctoral Researcher, and NAN LI, Professor, are with The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081, China. Contact e-mail: [email protected] BAIKUAN LIU, Chief Executive Officer, and ZHONGYANG HE, Chief Research Officer, are with Puyang Refractories Group Co., Ltd., Puyang 457100, China. Manuscript submitted May 27, 2015. Article published online March 25, 2016. METALLURGICAL AND MATERIALS TRANSACTIONS B
material to replace natural graphite flake and decrease the amount of carbon in MgO-Al2O3-C and MgO-C refractories. Luo et al.[6] reported that addition of 0.05 wt pct multi-walled carbon nanotubes (MWCNTs) into Al2O3-C refractories resulted in an increase of mechanical properties, whereas they got deteriorated with the further increase of MWCNTs amount from 0.1 to 1 wt pct. However, in order to use nanoscale materials in refractories effectively, two key problems remain to be solved: First, a uniform distribution of the nanoscale materials in the matrix is required, and second, the price of the nanoscale materials must be reduced. Geol et al.[7] prepared an Al2O3 + graphite + nanocarbon composite by means of mechanical dispersion and surface functionalization, and the enhancement of thermal shock resistance of Al2O3-C refractories was obtained by adding this composite. Recent investigations had shown that when Al2O3-CNT composites were introduced into ceramics as starting materials, the mechanical properties and wear resistance of ceramic/CNT nanocomposites could be improved to some extent.[8–11] Up to now, the Al2O3-CNT composites had prepared using various mixing methods, but it was difficult to obtain a highly uniform distribution of CNTs in the composites. In this study, a novel method of preparing MWCNTs containing Al2O3-C refractories had been developed by introducing Al2
Data Loading...
