作者：A.G.M. Othman;W.M.N. Nour;M.M.S. Wahsh;

作者单位：National Researche Centre, Refractories, Ceramics and Building materials Dept., Cairo, Egypt;National Researche Centre, Refractories, Ceramics and Building materials Dept., Cairo, Egypt;National Researche Centre, Refractories, Ceramics and Building materi

刊名：The Refractories Engineer

ISSN：1362-4547

出版年：2010-01-05

卷：2010

期：1

起页：14

止页：20

分类号：TQ175.7

语种：英文

关键词：

内容简介

CaZrO_3-BCa_2SiO_4-C composite refractories was used to prevent and/or reduce of nozzle clogging by the formation of liquid calcium aluminate phases. While, graphite was responsible for improving the thermal shock resistance and non-wetability of the refractory composition by slag and molten steel. The effect of different grain size of the batches based on CZ-βC_2S and graphite on the densification parameter, cold crushing strength and thermal shock resistance of the investigated samples were studied. Also, the oxidation resistance test was examined for the samples before and after addition of B_4C as antioxidant. Phase composition of the samples was tested by X-ray diffraction (XRD). Also, microstructure and microanalysis of the samples were examined. It was observed that; the batches having to higher content of medium grain size exhibit the good results of bulk density and apparent porosity as well as cold crushing strength according to the well packing of grains which leads to good sintering on firing. On the other hand, batches containing higher amount of carbon exhibit low densification in comparison with the lower one. Also, B_4C enhanced the oxidation resistance of the investigated samples by the formation of the liquid calcium boron silicate phase. The latter phase formed a barrier to passage of oxygen to elemental carbon within the body of the refractory compositions in which achieved higher resistance to oxidation. In addition, all batches achieved excellent thermal shock resistance. Accordingly, brick Bl containing (34.83% coarse, 26.87% medium and 29.85% fine grains from CZ-BC_2S and 7.96% graphite as well as 0.5% B_4C) exhibits excellent technological properties and then recommended for use as anti-clogging nozzle refractory material in steelmaking