含铝粉的MgO-SiC材料对钢水的增碳行为

分别以93%或96%的电熔镁砂(3~1mm,≤1mm,≤0.088mm)、4%的碳化硅粉(≤0.088mm)、3%或0的金属铝粉(≤0.088mm)为主要原料,配成含铝粉和不含铝粉的MgO-SiC试样,以热固性酚醛树脂为结合剂,在等静压压力机上以200MPa的压力压制成坩埚,自然养护24h后于230℃保温24h,然后在坩埚中加入5kg超低碳钢,并在钢样表面覆盖120g无碳保护渣,放入感应炉中加热至1600℃至钢水熔化,每隔30min取1份钢样,共取6份,化验钢样中的碳含量,并对试验后试样与钢水的反应层进行显微镜观察和EDAS分析。结果表明:SiC氧化形成的SiO2保护膜以及MgO-CaO-SiO2液相的形成,有利于降低SiC对钢水的增碳作用;金属铝粉的加入减少了SiC的氧化,并且可能对钢水产生脱氧作用,导致SiC向钢中增碳。     

Effect of nanocarbon sources on microstructure and mechanical properties of MgO–C refractories

A study of microstructural evolution, mechanical and thermo-mechanical properties of MgO–C refractories, based on graphite oxide nanosheets (GONs), carbon nanotubes (CNTs) and carbon black (CB), was carried out by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS), three-point bending and thermal shock tests. Meanwhile, these results were compared to the conventional MgO–C refractory containing 10 wt% flaky graphite prepared under the same conditions. The results showed that higher cold modulus of rupture was obtained for the composition containing GONs, and the composition containing CNTs exhibited larger displacement after coking at 1000 °C and 1400 °C. Also, the addition of nanocarbons led to an improvement of the thermal shock resistance; in particular, both compositions containing CNTs and CB had higher residual strength ratio, approaching the thermal shock resistance of the reference composition containing 10 wt% flaky graphite, as it was associated with the presence of nanocarbons and in-situ formation of ceramic phases in the matrix.     

National Quality Supervision &Inspection Center for Refractories

正National Quality SupervisionInspection Center for Refractories(NRQS)was set up in 1986 and was authorized in 1990 by State Bureau of Quality and Technical Supervision(SBQTS)as the state supervisioninspection center(Certificate SBQTS No.101).In 1993,NRQS was granted ImportExport Authorized Laboratory for national refractories by the State Administration for Entry Exit Inspection and Quarantine(Certificate No.5302).In 1995,NRQS was granted the     

影响镁炭质捣打料导电性的因素

研究了不同热处理温度下,石墨含量及颗粒尺寸、结合剂加入量及种类和金属粉末对镁炭质干式捣打料导电性能的影响。认为随着热处理温度的提高,捣打料的电阻率降低。经800℃以上处理的某些材料,其电阻率可达到10-4·m;石墨含量增大,电阻率下降;酚醛树酯是导电材料的良好结合剂,但引入部分沥青,亦能满足实用要求;金属粉末对导电性的提高无明显贡献。     

电熔耐火材料的无损检测

介绍了电熔耐火材料无损检测的重要性,超声检测和微波检测的原理,方法和装置,以及国外关于电熔耐火材料无损检测的概况。     

钒铁冶炼炉氧化铝渣的性能分析

为了探索钒铁冶炼炉氧化铝渣用于耐火材料的可能性,选取完整的氧化铝渣渣饼,剖开后根据其断面不同区域的颜色和致密度分层取样,检测其理化性能、物相组成、颗粒(5~3 mm)强度及水硬特性。试验结果表明:氧化铝渣饼大致可分为三层:以MgO为主要成分(质量分数为83.89%)的镁砂层,以镁铝尖晶石、方镁石和二铝酸一钙为主晶相的变质层,以二铝酸一钙和镁铝尖晶石为主晶相(二者的体积分数之和在80%以上)的主渣层;各渣层的耐火度大于1 790℃,体积密度大于3.0 g·cm-3,吸水率≤2.4%;主渣层的颗粒强度与焦宝石的接近,具有水硬性。综合来看,氧化铝渣可用于耐火材料。     

硅溶胶结合不定形耐火材料的研究及应用现状

总结了硅溶胶结合不定形耐火材料(包括浇注料、捣打料、喷射料和压入料)的性能研究和应用现状,并展望了硅溶胶结合耐火材料技术研究的方向和前景。     

受钢工况钢包壁应力场的模拟与分析

ANSYS程序是进行热和结构分析的好工具,它在钢包上的应用非常广泛。以钢包二维截面为研究对象,分别讨论受钢工况下耐火材料物性参数和不同的工作层厚度对包壁应力场分布的影响,从而为钢包设计提供一些依据。     

包钢用主要不定形耐火材料的种类与特性

综述了目前包钢用不定形耐火材料种类,主要有耐火浇注料、可塑料.捣打料、干式料、喷补料、投射(补)料、涂抹(喷涂)料、压入料、耐火泥浆和预制件等,并简要介绍了不定形耐火材料的生产工艺、常用结合剂及特性.