Refractories for handling steel outside a furnace

A range of refractories is presented for handling steel outside a furnace, which are produced by the Borovichi Refractories Corporation. The refractory characteristics and working features are given. Translated from Novye Ogneupory, No. 9, pp. 29–35, September, 2008.     

水蒸气对氮化烧成制品的影响

利用硅和氮直接合成氮化硅,并用其作为结合相生产氮化硅-碳化硅制品时,氮化炉中水蒸气浓度过大（＞0．7％）的话,对制品的质量会产生诸多不良影响。     

Binders for compacting the products based on nonplastic materials

Conclusions We studied the effect of various components of the binders on the properties of the press-powders and the semifinished products. The binder of the obtained composition can be used for preparing press-powders from nonplastic materials.Translated from Ogneupory, No. 4, pp. 22–24, April, 1986.     

对真空感应炉中二次炼钢用耐火材料的侵蚀性研究

采用一种优化的侵蚀性测试方法,模拟了真空炉内温度、熔渣成分和超低的压力条件,测试在真空感应炉内进行,并且分析了MgO-C砖的损毁机理。通过对测试后样品进行比较性分析,确定了本研究的可靠性。     

Heat stability of sintered composite materials based on titanium carbide

The method of residual strength is used to study the thermal stability of sintered cermet composite materials based on TiC. It is shown that the thermal stability and the coefficient of variation of the residual strength depend strongly on the chemical composition of the metallic binder and the volume fraction of the carbide phase in the material. It is inferred that the value of the compressive stresses in the bulk of the material is a determining factor for the thermal stability of the composite material, which depends in turn on the difference in the coefficients of thermal expansion of the carbide and metallic phases.     

转炉钢渣代铁渣配料生产水泥熟料的应用

我厂现有Φ2.8m×10m及Φ2.5m×10m机立窑2台,生料采用石灰石、黏土、铁渣和白煤四组分全黑生料配料,产品质量稳定。2004年初以来,由于铁渣供应紧张,价格不断上涨,我们采用了转炉钢渣部分替代铁渣,在生产线上进行了工业试生产。通过不断摸索和改进,2004年8月份开始正式投入使用     

以水泥为基材制备特高强复合胶凝材料

论述了以水泥为基材制作高强复合胶凝材料的制备工艺、增强增韧机理及其存在的问题。     

Machining the refractories and constructing the lining of equipment for the vacuum treatment of steel

Conclusions A section has been organized at the Magnezit Plant for the machining and checkout assembly of MKhVP and MKhV refractories for VTS equipment. The section is equipped with a column- and-knee type milling machine, surface grinders, and stands for the checkout assembly of the bottom and roof of the vacuum chamber and the hood cover.The masonry elements are shaped and a high quality of masonry work for the lining of VTS equipment is achieved by cutting and grinding the refractory bricks with diamond tools during a checkout assembly of the masonry. A total of 30–50% of the bricks used in the lining are machined in this manner.The tools are AOSK-type diamond disk saws for cutting and a face-plate built up of diamond-bearing bars for grinding the refractories. The bonding substances of the tools is a hard alloy (M50). The granularity and concentration of the diamonds are not significant factors in the machining productivity and the finish of the machined surface. The refractories are machined without a coolant feed in the cutting zone.An investigation was carried out of the principal cutting parameters for magnesia refractories. The conditions for dry-machining refractories with an AOSK-type diamond disk saw bonded with M50 are as follows (horizontal feed of the work to the tool): cutting speed, 46–50 m/sec; feed, 0.8 m/min; depth of cutting, 60 mm; productivity, 480 cm²/min; and diamond consumption, 10–12 carat/m².Translated from Ogneupory, No. 7, pp. 17–24, July, 1977.     

Some distinctive features of structure formation in materials based on sintered silicon nitride

Special features of formation of the microstructure and phase composition of sintered materials based on Si₃N₄ and α-sialons synthesized in the Si - Y - Al - O - N system by the method of compressive and microwave sintering are described. It is concluded that the morphology of the initial Si₃N₄ powders, the phase composition of the initial mixture, and the sintering technology of the ceramics in the decisive stage determine its microstructure, including the processes of self-reinforcement by β-Si₃N₄ crystals, the phase composition, and the physicomechanical characteristics. Translated from Ogneupory i Tekhnicheskaya Keramika, No. 7, pp. 28 – 31, July, 2000.     

Refractories based on fused pe riclase — Chromite material for vacuum steel refining plants

Conclusions The relevant technology was developed and production has started of high-quality refractories based on a high-density fused periclase —chromite material.The refractories are characterized by a low content in silica and silicates, well-developed direct bonds between the high-refractoriness minerals, and high indices for density, cold-crushing strength, thermal strength, refractoriness under a load, and in-vacuo stability to the action of slag and steel melts and the gases. The most favorable combination of properties was achieved when using starting materials of high-purity, fused periclase-chromite with a maximum grain size of 5 mm, batches with a low content of fine-ground components, high specific molding pressures, high firing temperatures, and long holding times at the peak temperature.The refractories are designed for the lining of the pipe, bottom, and walls of the chamber of equipment for vacuum steel refining and can be used with good results in the lining of converters, electric-arc and plasma furnaces, and other installations for melting high-temperature materials.Translated from Ogneupory, No. 8, pp. 5–12, August, 1976.