精炼合成渣对盛钢桶耐火材料的侵蚀

在巴西优质钢的生产中，经常使用许多种类的精炼合成渣，目的在于：①吸收氧化铝非金属杂质；②对钢水脱硫；③保护钢水液面不再氧化；④隔热。合成渣是一种石和荧石的混合物，本文比较研究了合成渣组成对盛钢桶耐火材料蚀损的影响。选用的合成渣是：①石灰和荧石的混合物；②石灰和荧石的混合物，并饱和有氧化镁；③（ＣａＯ－ＳｉＯ２－Ａｌ２Ｏ３－ＭｇＯ）系合成渣。研究结果表明，氧化物系合成渣对耐火材料的侵蚀较小，达到了研     

DOFASCO厂炉外精炼钢包用耐火材料

该文章将介绍ＤＯＦＡＳＣＯ厂过去五年内对炉外精炼钢包用耐火材料做的一些改进，并要对下列题目进行论述：（１）整体钢包衬结构；（２）渣线改进；（３）包壁的改进；（４）包底的改进。     

炉外精炼渣碱度及Al2O3含量对镁铬耐火材料侵蚀的影响

本工作采用旋棒法研究了镁铬耐火材料在不同碱度和不同Al_2O_3含量的炉外精炼渣中的溶解动力学。结果表明:熔渣的CaO/SiO_2值越高,镁铬材料的溶解速度越小,但高CaO/SiO_2渣使试样粉化,故CaO/SiO_2≈1.2时,损毁程度最轻。熔渣Al_2O_3含量对侵蚀的影响因CaO/SiO_2值不同而各异。     

钢包精炼渣对不同MgO基耐火材料的侵蚀研究

利用感应熔炼炉研究了低碱度钢包精炼渣对钢包渣线部位常用的3种MgO基耐火材料(镁碳、镁碳化硅、镁尖晶石)的侵蚀,同时利用黏度试验研究了耐火材料的基质组分与熔渣混合后形成新渣相的黏度变化。研究结果表明:1)低碱度炉渣在与MgO基耐火材料中的MgO接触过程中会形成低熔点物相钙镁橄榄石(CMS),与镁铝尖晶石接触会促进钙铝黄长石(C2AS)的生成而使渣黏度增加,处于熔渣区域的SiC被氧化成SiO2而提高渣的黏度。2)熔渣对耐火材料的侵蚀程度取决于熔渣和耐火材料之间的润湿情况,熔渣黏度的增加只是在一定程度上缓解了熔渣对耐火材料的侵蚀,反应层的耐火材料在钢水和熔渣的冲刷下仍会流失到熔渣中去。     

钢包炉和炉外精炼用耐火材料与造渣系统：第10部分

从传统角度来看,炉渣及耐火材料在炼钢过程中,除非影响产量,否则大部分都被忽略。通过把钢-渣耐火材料看作是一个相互作用的系统,了解必要的组成与过程有关的调整及冶金要求,就可以以较低的价格生产出较好     

钢包炉和炉外精炼用耐火材料与造渣系统：（第16部分）

1 炉渣的要求与操作方法的选择 钢包炉炉渣的作用如下。 ①为熔池隔热,保持钢水的温度;②熔化并吸收钢水中的杂质;③防止钢水氧化,有助于控制钢的化学成份;④通过吸收硫,提高钢水的质量;⑤稳定电弧,避免由于电弧不稳对耐火材料造成的损坏;⑥与耐火材料相容,将     

洁净钢炉外精炼与连铸用耐火材料及其发展

简述了洁净钢炉外精炼与连铸用耐火材料的现状及发展方向,主要介绍了精炼钢包系统、RH精炼系统、中间包系统用耐火材料的材质选择及技术进步,同时强调了耐火材料的管理及创新在洁净钢生产中的作用。     

炉外精炼用耐火材料提高寿命的途径及其发展动向

结合VOD与RH介绍了造成炉外精炼蚀损严重部位的原因。从MgO-Cr2O3、MgO-CaO、MgO-C、MgO-CaO-C、MgO-MgO·Al2O3等耐火材料性能及在精炼中的作用介绍了如何选择耐火材质;从接触角、熔渣粘度、形成高熔点化合物、气孔微细化以及炉渣成分控制、双饱和与精炼温度等方面介绍了提高炉外精炼用耐火材料寿命的途径。最后结合镁铬、镁钙、MgO-C、镁钙碳与无铬耐火材料介绍了炉外精炼用耐火材料的发展动向,并对MgAlON结合镁质耐火材料在炉外精炼中的研究与应用进行了评估与预期。     

计算机分析Al2O3-SiO2系耐火材料的抗FeO侵蚀性能

采用C Builder编制程序绘制了 16 0 0℃下FeO -Al2 O3-SiO2 三元系等温截面图 ,在此基础上 ,判断不同组分的Al2 O3-SiO2 系材料抗FeO侵蚀能力的优劣。该程序具有界面好、使用便捷、准确的特点。     

纳米ZrO2对MgO-CaO材料烧结及抗热震性的影响

在≤0.1mm的MgO-CaO砂中分别加入占其总质量2%、4%、6%和8%的纳米ZrO2,分别经干混、压制成型,1600℃3h煅烧后,检测其体积密度和抗热震性,并进行XRD和SEM分析,以研究添加纳米ZrO2对MgO-CaO材料烧结和抗热震性能的影响及其作用机理。结果表明:添加2%的纳米ZrO2即可显著提高MgO-CaO材料的烧结程度和抗热震性;综合考虑MgO-CaO材料的烧结程度和抗热震性认为,添加6%的纳米ZrO2可使材料获得良好的性能。     

含ZrO_2添加剂对方镁石-尖晶石耐火材料抗渣性能的影响

采用电熔镁砂、电熔镁铝尖晶石为主要原料,用坩埚法研究了三种含ＺｒＯ２ 添加剂对方镁石－ 尖晶石耐火材料抗渣性能的影响。结果表明：引入的ＺｒＯ２ 能有效吸收渣中的ＣａＯ,形成高熔点的ＣａＺｒＯ３ 固相堵塞在气孔中,阻止了炉渣的进一步渗透,又有效地降低了ＣａＯ 对尖晶石的分解作用及ＣａＯ、ＳｉＯ２ 等对主晶相方镁石的侵蚀作用;同时,ＺｒＯ２ 的引入能促进烧结,提高高温固相直接结合率,对提高抗渣性也有着十分重要的意义。     

Al2O3-SiC-C耐火材料抗CaO-SiO2-K2O渣侵蚀性能研究

研究了Al2O3-SiC-C耐火材料的抗CaO-SiO2-K2O渣侵蚀性能,以及添加Cr2O3对Al2O3-SiC-C材料抗渣侵蚀性能的影响.研究结果表明CaO-SiO2-K2O熔渣对Al2O3-SiC-C材料具有明显的侵蚀作用;在Al2O3-SiC-C材料中添加适量的Cr2O3可以有效地抑制CaO-SiO2-K2O熔渣向耐火材料内部的渗透,降低耐火材料的侵蚀速度.     

Comparative evaluation investigation of slag corrosion on Al2O3 and MgO-Al2O3 refractories via experiments and thermodynamic simulations

Al₂O₃- and MgO-based refractories are widely used in the steel industry as lining materials for many metallurgical reactors. Due to their direct contact with slag and steel, they suffer corrosion and degradation, especially in the slag-line position, which limits their service performance. The purpose of this article is to obtain a better understanding of the corrosion behavior of the two refractories with different compositions of virtual steelmaking slags (wt%CaO/wt%SiO₂ = 3.0–7.0, Al₂O₃: 18–35 wt%) using laboratory experiments and FactSage thermodynamic modeling. Pure Al₂O₃ and MgO-Al₂O₃ crucibles were adopted to simulate the two refractories, respectively, during the experiment. The results show that the degree of corrosion of both crucibles increases with an increase in slag basicity and a decrease in Al₂O₃ content in the slag. The Al₂O₃ crucible is more susceptible to corrosion than the MgO-Al₂O₃ crucible, which is attributed to the effect of the slag penetrating through the Al₂O₃ crucible matrix and substituting part of its matrix. For the MgO-Al₂O₃ crucible, there was no obvious slag substitution, but a transition layer was found in the contact region between the crucible and the slag. The Al₂O₃ in the crucible matrix reacts with slag to produce calcium alumina (CaAl₁₂O₁₉, CaAl₄O₇) and other complex oxides, while the MgO particles at the MgO-Al₂O₃ crucible-slag interface were only surrounded by liquid slag without an obvious chemical reaction between them. The mechanism of corrosion was studied by experiments combined with thermodynamic calculations and with the establishment of a new corrosion model. This study is expected to provide a guide for the design of related refractories and slags in industrial applications.     

电熔锆刚玉对Al_2O_3-SiO_2系浇注料抗铅渣侵蚀性的影响

以特级高铝矾土(粒度为8～5、5～3、3～1和≤1 mm)为骨料,电熔棕刚玉粉(≤0.044 mm)、α-Al2O3微粉(≤5 μm)和SiO2微粉(≤1μm)为细粉,铝酸钙水泥(Secar 71)为结合剂制备了卡尔多炉直升烟道用Al2O3-SiO2系浇注料.用电熔锆刚玉粉(≤0.044 mm)部分替代棕刚玉粉,采用静态坩埚法(1 300℃5 h,空气气氛)研究了添加物电熔锆刚玉的加入量(质量分数分别为4%、8%、12%、16%)对Al2O3-SiO2系浇注料抗铅渣性的影响,对抗渣前后试样的显微结构进行了分析.结果表明:加入锆刚玉后,浇注料的抗铅渣性能得到明显改善,其适宜加入量为8%;显微结构分析表明,铅渣对Al2O3-SiO2系浇注料的侵蚀主要表现为铅渣中的PbO与Al2O3-SiO2系浇注料中的SiO2、CaO反应,生成硅酸铅或铅酸钙等低熔物而导致浇注料的损毁;而浇注料的添加物锆刚玉中的ZrO2未与PbO反应,从而使浇注料表现出良好的抗铅渣侵蚀性.     

Study on the corrosion resistance of cordierite-mullite and SiC refractories to Li-ion ternary cathode materials

The corrosion reactions of Li-ion ternary cathode material on cordierite-mullite and SiC refractories were studied at 780 °C for 20 h. The XRD and SEM technologies were used to study the corrosion process. The results showed that the interaction between Li₂O and cordierite-mullite material produced a large number of reactants, which led to the failure of cordierite-mullite refractories. For SiC refractories, a small amount of SiO₂ were formed by the SiC oxidation reaction, then the SiO₂ reacted with Li₂O to form lithium silicate compound. Moreover, Li₂O tended to diffuse into the interior of SiC refractory slabs through pores, which avoided the formation of a large amount of reaction products and gave good corrosion resistance to the material without damaging its structure. It has been found that the corrosion resistance of the two materials can be effectively improved by the alumina sol impregnation method.     

Effects of La2O3 on the viscosity of copper smelting slag and corrosion resistance of magnesia refractory bricks

The rotating method is carried out to investigate the effects of La₂O₃ content (0–4 wt%) on the viscosity of copper smelting slag at high temperatures, the apparent activation energy is evaluated according to the Arrhenius equation and the structural characterization of this quenched slag is characterized by Raman spectroscopy. Meanwhile, the corrosion resistance of copper smelting slag with different content of La₂O₃ on magnesia refractory bricks is researched by employing a static crucible method. The experimental results show that the viscosity of copper smelting slag decreased with the La₂O₃ ratio increases from 0 to 3 wt% in a certain temperature range, which is because La₂O₃ simplifies the structural units of [SiO₄] tetrahedral groups. However, the melt viscosity increases after add 4 wt% La₂O₃, the reason is that more La₂O₃ addition improves the structural compactness of [SiO₄] tetrahedral groups in the molten slag due to the strong accumulation effect of La³⁺. Observation of the corroded samples found that the corroded magnesia refractory brick has a lower penetration index when the copper smelting slag with the content of 4 wt% La₂O₃. Therefore, the copper smelting slag containing 4 wt% La₂O₃ has a higher viscosity, and thus impeded the penetration behavior of copper smelting slag on magnesia refractory bricks.     

Effects of different particle size of spinel and Y2O3 additive of the periclase-spinel refractory on the sintering densification and corrosion resistance to copper smelting slag

In order to analyze the sintering densification and copper smelting slag corrosion resistance of periclase-spinel refractories, the periclase-spinel refractories were prepared with fused magnesia, magnesia-rich spinel, industrial alumina, and yttrium oxide as the main raw materials. The different particle sizes of spinel in material and with or without Y₂O₃ additive were studied. The study demonstrated that: (1) The different particle sizes of spinel in periclase-spinel refractories can result in different effects. Adding particle spinel to the refractory can improve the strength and corrosion resistance of the periclase-spinel refractories. The addition of spinel and magnesia powders in the matrix resulted in cracks due to the great difference of coefficient of thermal expansion between magnesia and spinel. The reduction in bulk density and strength of the material decreased slag penetration resistance because of its poor sintering properties. While adding the alumina in the matrix can further fill the crack and prevent slag penetration by the volume expansion of in-situ reaction to form spinel. (2) The periclase-spinel refractories can be reacted with Cu slag to form a Mg₂FeO₄ insulating layer as the iron ion becomes oxidized. Adding Y₂O₃ in periclase-spinel refractories can result in grain boundary phase reconstruction, which can promote sintering densification, improve the slag physical infiltration resistance, and improve the chemical corrosion resistance of materials.     

Effect of CaO/SiO2 ratio on phase transformation and properties of anorthite-based ceramics from coal fly ash and steel slag

Anorthite-based ceramics were produced entirely from coal fly ash and steel slag. The effect of the CaO/SiO₂ ratio (0.12–0.8) on the phase transitions was examined by adding steel slag to coal fly ash in the range of 10–50 wt%, and a temperature range of 900–1200 °C. The influence of CaO/SiO₂ and sintering temperatures on the technological properties were assessed by response surface methodology (RSM) and correlated with the phase changes. The results revealed that anorthite was the main phase for the CaO/SiO₂ ratio ranging from 0.12 to 0.56, while at 1200 °C, a ratio of 0.8 involved a high content of gehlenite. RSM showed that the CaO/SiO₂ ratio was the main influencing factor on the density, while the variation of apparent porosity and compressive strength were more affected by sintering temperature. The crystallisation of the anorthite phase significantly enhanced the properties of the obtained ceramics, whereas the appearance of gehlenite reduced the mechanical strength. The optimum conditions to fabricate anorthite-based ceramics with suitable properties were found to be a CaO/SiO₂ ratio of 0.46 and a temperature of 1188 °C. The optimised anorthite-based ceramic exhibited a low thermal conductivity (0.39 W/m.K) and a dielectric constant of 6.03 at 1 MHz, along with a compressive strength of 41 MPa, which makes this sample a potential candidate for insulator applications.