Novel Ti2O3–Al2O3 raw materials with controllable Ti2O3 content from the aluminothermic reduction of ilmenite

Titanium-containing refractories have excellent performance, but the high cost limits their application. A series of Ti₂O₃–Al₂O₃ raw materials with different Ti₂O₃ contents were prepared by aluminothermic reduction of ilmenite, while the generated ferrotitanium alloy can be used as raw materials for special steels. Regulating the amount of aluminum added in the system regulates the degree of titanium reduction, and the formed ferrotitanium alloy can achieve separation from the oxides. With decreasing aluminum content of, the Ti₂O₃ content increased, and the continuous distribution of the corundum area decreased, resulting in a continuously distributed Ti₂O₃ area. Our results indicated that the molar ratio of aluminum to ilmenite should be higher than 1.4 to achieve slag iron separation. The reaction model for the aluminothermic reduction was established, and the formation mechanism of Al₂O₃ and Ti₂O₃ in the system was discussed.     

熔融还原炼铁用耐火材料的研究现状

综述了国内外熔融还原炼铁用耐火材料的研究现状。讨论了熔融还原技术的工艺特，点及其耐火材料的使用条件。分析了目前已基本成熟的ＣＯＲＥＸ工艺的耐火材料的使用现状及存在问题，和铁浴式熔融还原炉用耐火材料的研究现状，存在问题及前景。     

高铝-尖晶石-炭不烧水口砖的研制及应用

以高铝矾土熟料、烧结合成镁铝尖晶石砂为主要原料，加入5％～10％鳞片状石墨，外加6％甲阶酚醛树脂为结合剂，可制得气孔率低、体积密度高、强度大、抗热震、耐侵蚀的高铝－尖晶石－炭质不烧水口砖。     

高铝水泥及含高铝水泥耐火材料中Al_2O_3的化学分析方法

提出了测定高铝水泥及含高铝水泥的耐火材料中Al2O3的化学分析方法,并把该方法与“粘土、高铝质耐火材料化学分析方法”及“高铝水泥化学分析方法”做了对比。采用本方法分析高铝水泥及含高铝水泥的耐火材料中Al2O3含量,具有准确、简便等特点。     

钢铁冶金工艺新进展及其耐火材料问题

重点介绍了熔融还原和近终形连铸连轧技术的进展，并指出其在耐火材料应用上存在的某些问题。     

两种荷重软化温度检验方法测试结果的分析

分析了ＹＢ３７０—９５荷重软化温度检验方法（又称直接升温法）与ＧＢ５９８９—８６致密定形耐火制品荷重软化温度检验方法（示差－升温法）测试结果不同的原因和差值范围。结果表明示差－升温法能较好地消除设备及人为因素造成的误差，更能反映耐火制品的真实值。     

High temperature mechanical properties of porous Si3N4 prepared via SRBSN

The high temperature strength and fracture behavior of porous Si₃N₄ ceramics prepared via reaction bonded Si₃N₄ (RBSN) and sintered reaction bonded Si₃N₄ (SRBSN) were investigated at 800–1400?°C. The weight gain after oxidation for 15?min and the microstructure of the edge and center of the fracture surface clearly show that the internal oxidation of porous SRBSN is unavoidable with porosity of ~ 50% and mean pore size of 700?nm. The oxidation of Si₃N₄ and intergranular Y₂Si₃O₃N₄ phase may responsible for the high temperature strength degradation of SRBSN. Porous Si₃N₄ ceramics prepared with addition of 1?wt% C showed low strength degradation at temperature >?1200?°C.     

基质优化和组合以改善浇注料性能

通过优化基质中煅烧氧化铝或活性氧化铝、铝酸钙水泥、外加剂、板状刚玉细粉(或其他细粉 )的组成 ,可明显改善浇注料的性能 ;采用优化的基质体系 (MAS) ,可获得施工时间可控、加水量低 (振动浇注料为 3 .6 %～ 4.6 % ,自流浇注料为 4.0 %～ 5 .0 % )的高强度自流或振动浇注料 ,实现浇注料配方设计的菜单化 ;高稳定性美铝组合基质 (AIM)的出现 ,进一步简化了浇注料的配方设计 ,使同一种基质可满足振动或自流施工的作业要求 ,并可通过骨料替换获得不同性能的浇注料以满足不同的使用要求     

Thermal conductivity of high porosity alumina refractory bricks made by a slurry gelation and foaming method

Alumina has high heat resistance and corrosion resistance compared to other ceramics such as silica or mullite. However, for its application to refractory bricks, its high thermal conductivity must be reduced. To reduce this thermal conductivity by increasing the porosity, a GS (gelation of slurry) method that can produce high porosity solid foam was applied here to produce the alumina refractory brick. This method was successfully applied to produce alumina foam with high porosity and thermal conductivity of the foam is evaluated. At room temperature, the thermal conductivity was about 0.12 W/mK when the foam density was 0.1 g/cm³. At elevated temperature above 783 K, thermal conductivity of the foam was strongly affected by heat radiation and increased with increasing temperature, in contrast to the thermal conductivity of alumina itself, which decreased with increasing temperature. The alumina foams developed here achieved sufficient thermal insulating properties for use in refractory bricks.     

基质组成对高铝质浇注料荷重软化温度的影响

研究了基质组成对低水泥高铝质浇注料荷重软化温度的影响。结果表明 ,在骨料组成不变的情况下 ,以纯铝酸钙水泥取代复合水泥以及分别在基质中引入适量蓝晶石、α Al2 O3微粉和莫来石 ,浇注料的荷重软化温度均有显著提高     

Effect of Al2O3-SiO2 substrate on gas-sensing properties of TiO2 based lambda sensor at high temperature

Alumina is widely used as substrate material for oxygen lambda sensors. It has been reported that response properties of sensors are highly dependent on surface state of substrates. In this work, Al₂O₃-x%SiO₂ (x = 2–30) substrates were specially prepared for TiO₂ based lambda sensors for high temperature operation. Structure and surface state of prepared substrates were characterized by XRD, SEM and XPS. TiO₂ sensing film was prepared by screen printing method. Results indicated that sensors fabricated on Al₂O₃-10%SiO₂ substrate exhibited the best sensing properties. Moreover, final steady-state voltages of all sensors were limited to less than 100 mV at 600–800 ℃.     

“耐高温挡边输送带”专利获欧盟授权

目前使用的耐高温挡边输送带一般包括基带、以及设置在基带上方的横隔板和横隔板两侧的裙边,横隔板包括其上方的倾斜挡边和底部底座。由于该种输送带为橡胶制品,刚性较差,其横隔板和裙边只能通过二次硫化的方法固定在基带上方,这种硫化的连接方式存在不耐高温、不耐老化等缺点。另外,由于横隔板和裙边的强力不足、刚性较差,因此导致横隔板和裙边在使用中经常脱落,使得该产品的使用寿命较低,成本较高。     

水性耐高温抗氧化无机涂料

研制了一种水性单组份常温干燥无机、防止钢坯脱碳和抗氧化的耐高温涂料。论述了钢坯在高温下的氧化机理及防护涂料发展趋势和要求。并对产品的试验结果进行了分析。     

不同脱碳层厚度的A3F钢板与高温瓷釉密着性研究

不同脱碳层厚度的Ａ＿３Ｆ钢板与高温瓷釉密着性研究王禹,胡德林,邵引年（西北工业大学７１００７２）（西北轻工业学院７１２０８１）ＡＳｔｕｄｙｏｎＡｄｈｅｒｅｎｃｅｂｅｔｗｅｅｎＡ＿３ＦＳｔｅｅｌｗｉｔｈＤｉｆｆｅｒｅｎｔＤｅｐｔｈｏｆＤｅｃａｒｂｕｒｉ...     

高温乳浊白釉的研制

以锆英石为乳浊剂，研制出烧成温度大于1300℃，白度大于80，符合国标的高温乳浊白釉，并借助于OM，SEM，XRD等手段，系统研究了该釉的工艺条件和形成机理，结果表明，锆英石最佳引入量为9％－13％，SiO2:Al2O3值为7．32：1；釉层中主要晶体为硅酸锆和石英，影响釉面效果的主要因素有釉料组成，粒度，乳浊剂和熔剂的引入量，SiO2:Al2O3的比值，烧成制度等。     

High temperature fracture toughness and residual stress in thermal barrier coatings evaluated by an in-situ indentation method

High temperature fracture toughness and residual stress are important for the evaluation of TBCs. In this paper, an in-situ high temperature indentation method was originally developed to investigate the high temperature fracture toughness and residual stress in a typical TBC, nanostructured 8?wt% yttria partially stabilized zirconia (YSZ) coating. The cracks caused by in-situ high temperature indentation tests were observed, and high temperature fracture toughness and residual stress were experimentally measured. The fracture toughness was measured to be 1.25, 0.91 and 0.75?MPa*m^1/2 at 25, 800 and 1000?°C, respectively. The residual stress was measured to be ? 131.3, ? 55.5 and ? 45.5?MPa, correspondingly. Moreover, the residual stress and fracture toughness both decrease with increasing environmental temperature. It is also found that the fracture toughness without consideration of residual stress is significantly larger than the intrinsic fracture toughness, which may result from the compressive stress state.     

高温大功率PTC材料研制

本文通过多元施主掺杂，以及添加CaCO3、增加耐压等方法，使（Ba－Ph）TiO3系PTC高温材料的PTC效应、大功率特性得以改善，并通过制备工艺的改进制出了居里温度240～360℃，功率密度达100W／cm2的高温大功率材料。