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- 2018
1450℃反应烧结Fe3Si-Si3N4复合耐火材料的相组成
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Abstract:
以Si粉和Fe3Si-Si3N4为原料，在高纯N2气氛下制备Si3N4/Fe3Si-Si3N4复合材料。氮化烧成后Si3N4结合Fe3Si-Si3N4复合耐火材料试样中物相为Si3N4、Fe2Si、FeSi和Si2N2O。其中Si2N2O含量约6%，且在试样中心和外部分布不均匀。Fe3Si-Si3N4原料是Fe3Si和Si3N4两相共存材料，热力学评估和材料的微观结构分析表明，Fe3Si和部分Si粉形成新的低熔点硅铁合金，使靠近试样表面部位的部分开口气孔被液态硅铁合金所堵塞或填充，试样中心部位的微量氧不能迁移至外部，N2中微量氧将Fe3Si-Si3N4原料中Si3N4氧化，形成Si2N2O包裹，导致试样中心Si2N2O含量比边缘部位高。Si2N2O的形成使体系氧分压降至Si3N4稳定存在的氧分压时，Si粉直接氮化形成柱状Si3N4，而非纤维状Si3N4，同时在1 450℃氮化烧成条件下，Fe的存在促进了α-Si3N4向β-Si3N4的转变。 The Si3N4 reaction-boned Fe3Si-Si3N4 composites were prepared in an atmosphere of highly pure nitrogen with Si powders and Fe3Si-Si3N4 particles as the raw materials. The phase composition turns out to be Si3N4, Fe2Si, FeSi and Si2N2O. The content of Si2N2O is about 6% and varies with the section of Si3N4 boned Fe3Si-Si3N4 block. By analyzing thermodynamics and microphotography of Si3N4, it is determined that Si2N2O comes from the oxidation of Si3N4. During the sintering, Fe3Si can transform to a low-melting-point ferrosilicon alloy with part of the Si powder dissolving into it. The molten ferrosilicon alloy, Fe2Si and FeSi, can fill or block the apparent pores and stop the diffusion of oxygen from central section to the marginal section. As a result, the oxygen reacts with Si3N4 of Fe3Si-Si3N4 generating more Si2N2O in central section of the block. The oxidation of Si3N4 costs the oxygen of the system and allows silicon to reacts with nitrogen directly generating columnar Si3N4, not fibrous Si3N4, which is completely different with silicon nitrodation mechanism in Si3N4 reaction-bonded Si. Meanwhile the existence of Fe α-Si3N4 transform to β-Si3N4 at 1 450℃.
| [1] | VLASOVA M V, LAVRENKO V A, DYUBOVA L Y, et al. Nitriding of ferrosilicon powders[J]. Journal of Materials Synthesis and Processing, 2001, 9(3):111-117. |
| [2] | CHUKHLOMINAL N, MAKSIMOV Y M, VITUSHKINA O G, et al. Phase composition and morphology of products of combustion of ferrosilicon in nitrogen[J]. Glass and Ceramics, 2007, 64(1):63-65. |
| [3] | RILEY F L. Silicon nitride and related materials[J]. Journal of the American Ceramic Society, 2000, 83(2):245-265. |
| [4] | KOMETAN I K, LIZUKA K, KAGA T. Behaviour of ferro-Si3N4 in blast furnace tapholemud[J]. Taikabutsu Overseas, 1999, 19(1):11-14. |
| [5] | KAGA T, KOMETAN I K, LIZUKA K. The reaction offerro-silicon nitride in carbon refractory[J]. Taikabutsu, 2002, 54(11):574-575. |
| [6] | CHEN J H, LI B, YU L Y, et al. Mechanism analysis of synthesizing Fe-Si3N4 by flash-combusting FeSi75[J]. Advanced Materials Research, 2010(105-106):59-62 |
| [7] | 祝少军. 氮化硅闪速燃烧合成机理研究[D]. 北京:北京科技大学, 2005. ZHU S J. Study on flash combustion synthesis mechanism of silicon nitride[D]. Beijing:University of Science and Technology Beijing, 2005(in Chinese). |
| [8] | 李斌. 闪速燃烧合成氮化硅铁机理及应应用研究[D]. 北京:北京科技大学, 2016. LI B. Investigation on mechanism and application of ferrous silicon nitride synthesized by flashing combustion[D]. Beijing:University of Science and Technology Beijing, 2016(in Chinese). |
| [9] | 秦海霞, 李勇, 孙加林, 等. 埋碳条件下氮化硅铁-刚玉复合材料的反应机理[J]. 硅酸盐学报, 2014, 42(9):1184-1188. QIN H X, LI Y, SUN J L, et al. Reaction mechanism of ferro-silico nitride-corundum composite with carbon embedded[J]. Journal of the Chinese Ceramic Society, 2014, 42(9):1184-1188(in Chinese). |
| [10] | LONG M L, LI Y, QIN H X, et al. Formation mechanism of Si3N4 in reaction-bonded Si3N4-SiC composites[J]. Ceramics International, 2016, 42(15):16448-16452. |
| [11] | 陈俊红, 孙加林, 洪彦若, 等, 铁元素在氮化硅铁中的存在状态[J]. 硅酸盐学报, 2004, 32(11):1347-1351. CHEN J H, SUN J L, HONG Y R, et al. Distribution status of ferro silicon nitride[J]. Journal of the Chinese Ceramic Society, 2004, 32(11):1347-1351(in Chinese). |
| [12] | SCIENCE M, SWT L. Review on reactions between silicon and nitrogen[J]. Journal of Materials Science, 1983, 18(4):951-967. |
| [13] | MOULSON A J. Review reaction-bonded silicon nitride:Its formation and properties[J]. Journal of Materials Science, 1979, 14(5):1017-1051. |
| [14] | ZIEGLER G, HEINRICH J, W？TTING G. Review relationships between processing, microstructure and properties of dense and reaction-bonded silicon nitride[J]. Journal of Materials Science, 1987, 22(9):3041-3086. |
| [15] | HEIKINHEIMO E, ISOMAKI I, KODENTSOV A, et al. Chemical interaction nitride ceramic between Fe and silicon[J]. Journal of the European Ceramic Society, 1997, 17(1):25-31. |
| [16] | 国家标准化管理委员会. 致密定形耐火制品体积密度、显气孔率和真气孔率试验方:GB/T 2997-2000[S]. 北京:中国标准出版社, 2001. Standardization Administration of the People's Republic of China. Test method for bulk density, apparent porosity and true porosity of dense shaped refractory products:GB/T 2997-2000[S]. Beijing:Standards Press of China, 2001(in Chinese). |
| [17] | 国家标准化管理委员会. 耐火材料常温耐压强度试验方法:GB/T 5072-2008[S]. 北京:中国标准出版社, 2009. Standardization Administration of the People's Republic of China. Refractories-Determination of cold compressive strength:GB/T 5072-2008[S]. Beijing:Standards Press of China, 2009(in Chinese). |
| [18] | 国家标准化管理委员会. 耐火材料定形耐火制品常温抗折强度试验方:GB/T 3002-2007[S]. 北京:中国标准出版社, 2001. Standardization Administration of the People's Republic of China. Refractory products-Determination of modulus of rupture at ambient temperature:GB/T 3002-2007[S]. Beijing:Standards Press of China, 2001(in Chinese). |
| [19] | 国家标准化管理委员会. 耐火材料高温抗折强度试验方法:GB/T 3002-2004[S]. 北京:中国标准出版社, 2004. Standardization Administration of the People's Republic of China. Refractory products-Determination of modulus of rupture at elevated temperatures:GB/T 3002-2004[S]. Beijing:Standards Press of China, 2004(in Chinese). |
| [20] | 徐功骅, 来月英, 刘艳生, 等, α-Si3N4晶须、晶柱与生长温度关系的研究[J]. 复合材料学报, 1996, 13(1):55-59. XU G H, LAI Y Y, LIU Y S, et al. Study of The relationship between alpha-Si3N4 whiskers, crystalline pillar and growth temperature[J]. Acta Materiae Compositae Sinica, 1996, 13(1):55-59(in Chinese). |
| [21] | QIN H X, LI Y, BAI L X et al. Reaction mechanism for in-situ β-SiAlON formation in Fe3Si-Si3N4-Al2O3 composites[J]. International Journal of Minerals Metallurgy and Materials, 2017, 24(3):324-331. |
