铝锆碳定径水口的研制与应用

本文介绍了一种新材质－铝锆碳质定径水口的研制和使用情况。     

铝锆碳质滑板研制

本文主要叙述了新型铝锆碳质滑动水口滑板的研制情况,简要介绍该耐材优良性能的机理剖析,研制过程的原料选择和工艺流程,试用结果表明,铝锆碳质滑板的使用寿命明显优于烧成铝碳质滑板,值得今后发展。     

锆质水口砖研究

本文对引进的用于有色浇注的小型锆质水口砖进行了显微结构分析。并对水口砖材料的物相组成及其分布。晶粒大小和形貌等进行了详细的观测。     

免烘烤铝碳质长水口的研制

采用优质耐火原料与科学配比,采用合理的燃气烧成制度并优化相应的制作工艺,保证成品热震稳定性和耐压强度的同时,解决了耐侵蚀性与使用寿命的矛盾,延长了使用寿命。     

含锆高纯高铝纤维及其制品的试制和应用

本文为高温工业炉窑节能工作需要,成功地研制出了性能优良的、含锆高纯高铝纤维新节能材料及制品,制品化学成份稳定、纤维交织充分、渣球率低、外观洁白、外形平整、有一定的弹性和抗拉强度,能在连续工作温度1350℃以下的高温炉窑上使用,并取得明显节能效果。     

铝锆偶联剂表面修饰稀土长余辉发光材料的研究

采用TL系列铝锆偶联剂对铝酸盐长余辉发光颜料(夜光粉)SrMgAl4O8:Eu2 、Dy3 进行表面改性.通过水解pH值、电导率、ATR-FTIR、XRF、SEM分别表征了改性前后试样的变化.结果表明:采用12%添加量的TL-1铝锆偶联剂在70 ℃下反应1.5 h,对长余辉发光颜料的改性效果最好,耐水性最佳;试样余辉衰减曲线表明,表面改性对其发光性能影响不大.     

免丙酮清洗脱模剂的研制与应用

１免丙酮清洗脱模剂的基本要求 （１）脱模性能好； （２）不损伤蜡料； （３）无丙酮； （４）沾浆效果好； （５）不腐蚀模具。２免丙酮清洗脱模剂组成物的选择 （１）选择润滑性能好的并不与蜡料产生化学反应的化工原料。达到较好的脱模性能，保证蜡模的完整性。 （２）选择表面张力小的化工原料。与蜡模表面上粘覆的脱模剂具有较强的亲和性和润湿性，以保证沾浆效果与涂挂性能处于最佳状态。 （３）选择防止腐蚀金属的化工原料。保证模具的完好性，提高其使用寿命。３免丙酮清洗脱模剂的应用试验 （１）制模试验。涂一次脱模剂，小件可…     

中碳低硅铝镇静钢连铸浸入式水口堵塞的原因分析及解决措施

结合浸入式水口堵塞物的分析,从钢水成分、顶渣、温度、精炼工艺、喂钙、连铸吹氩等多个方面,研究了中碳低硅铝镇静钢3种不同精炼工艺连铸浸入式水口堵塞成因。确定浸入式水口堵塞的主要原因有：水口吹气流量低不利于防止水口堵塞,顶渣氧化性强,加Al和上浮控制操作不规范,钙处理变性效果差,塞棒、板间、水口吹氩压力低。提出了适用于工业化生产的技术措施,工艺过程控制参数优化后,连浇炉数达到12炉以上。     

不断流快速更换中间罐浸入水口技术的研究与应用

根据中间罐使用寿命是浸入水口寿命2倍的情况，采用快速更换浸入水口的新工艺，延长中间罐使用寿命，将低耐火材料消耗，是高钢水收得率，降低浸入水口事故率，提高铸机作业率。     

小方坯定径包长寿技术的应用

莱钢小方坯定径包平均使用寿命在45 h,使用寿命偏低。对影响小方坯定径包使用寿命低的原因进行分析,通过设计应用高性能定径水口锆芯、定径上水口与快换滑块改型设计、定径水口快速对中安装技术、中包线下三级火焰烘烤脱模工艺及中间包在线快速富氧烘烤工艺等工艺措施,提高了小方坯定径包的使用寿命,实现定径包长周期连续稳态浇注,单包平均连拉周期达到70 h,降低生产成本,提高了钢水回收率,保障了生产稳定顺行。     

ZrO2—6Y2O3陶瓷中的类L12与L10有序结构

采用高分辨电子显微术、能量散射Ｘ射线谱及计算机模拟的方法,研究了烧结态时时效后的ＺｒＯ２－６Ｙ２Ｏ３陶瓷哪现的分别具有类Ｌ１２与类Ｌ１０有序结构的Ｙ０．２６Ｚｒ０．７５Ｏ２－ｘ与Ｙ０．５Ｚｒ０．５Ｏ２－ｙ相。     

Rapid sintering of nanocrystalline 8 mol.%Y2O3-stabilized ZrO2 by high-frequency induction heating method

Using a high-frequency induction-heating sintering (HFIHS) method, nanocrystalline 8 mol.%Y₂O₃-stabilized ZrO₂ was obtained from ultra fine powders. The observed advantages of this process include very quick densification to near theoretical density and prohibition of grain growth in nano-structured materials. Nearly fully dense nanocrystalline 8 mol.%Y₂O₃-stabilized ZrO₂, with a relative density of up to 99.8%, could be obtained with simultaneous application of 100 MPa pressure and an induced current within 10 min of sintering time without significant change in grain size. The influences of the sintering temperature and the mechanical pressure on the final density and grain size of the products were investigated. The hardness and fracture toughness of the dense ZrO₂ ceramics produced by HFIHS were investigated.     

Plastically deforming amorphous ZrO2-Al2O3

We report for the first time non-viscous, plastic deformation in an amorphous oxide: ZrO₂-Al₂O₃. Dense samples of amorphous ZrO₂-Al₂O₃ made by hot pressing spray-pyrolysed powder were deformed in uniaxial compression at 600–700°C at strain rates from 6×10⁻⁵ s⁻¹ to 10⁻³ s⁻¹. A transition from elastic to plastic deformation occurred at a critical stress ~360 MPa. The onset of plastic deformation was associated with a drop in the stress by 20–25%. Little influence of strain and strain rate on the flow stress was observed. The non-viscous, plastic deformation is related to the open structure of the amorphous phase as indicated by its low true density.     

Al2 O3与ZrO2复合粉涂层的组织形貌分析

利用大气等离子喷涂技术（ASP）在20号锅炉钢（20G）基体上制备Al2O3和ZrO2复合粉热障涂层（TBC）。通过X射线衍射分析（XRD）、扫描电镜（SEM）等观察分析了复合粉涂层表面形貌，分析了表面微裂纹和孔隙的形成过程。结果表明，涂层表面主要由α-Al2O3和t-ZrO2高温稳定相组成。复合粉涂层面层组织致密，Al2O3和ZrO2颗粒互熔在一起，从而提高了涂层的结合强度和致密度。     

Microstructure and mechanical properties of Al2O3/Er3Al5O12/ZrO2 prepared by a high-frequency zone melting method

Oxide directionally solidified eutectic ceramics (DSECs) have excellent mechanical properties, oxidation resistance, and ablation resistance in an ultra-high temperature environment above 1600 °C. In this study, Al₂O₃/Er₃Al₅O₁₂/ZrO₂ ternary DSECs were prepared by high-frequency induction zone melting. Their diameters were considerably greater than those of samples prepared with other processing techniques under the conditions where the microstructures were uniform. The component, microstructure, and mechanical properties in these samples were investigated. The results indicate that these DSECs were composed of only Al₂O₃, Er₃Al₅O₁₂, and ZrO₂ phases. As the solidification rate increased, both the eutectic phase size and eutectic spacing decreased continuously, and the microstructure was refined. The relationship between the eutectic spacing and solidification rate satisfied the formula λ²ν ≈ 33.8 ± 0.49. A polygonal colony structure appeared at a growth rate of 6.7 μm/s, which was associated with the uneven distribution of the temperature field. The hardness and indentation fracture resistance increased marginally with an increase in solidification rate, achieving 17.6 ± 0.8 GPa and 5.0 ± 0.5 MPa·m^1/2, respectively. The hardness of the Al₂O₃/Er₃Al₅O₁₂/ZrO₂ ternary DSEC was 18.3% less than that of the Al₂O₃/Er₃Al₅O₁₂ binary DSEC owing to the reduced hardness of the ZrO₂ phase added in the eutectic composition. The ternary DSEC's indentation fracture resistance was 88.4% greater than that of the binary eutectic ceramic owing to the phase transformation toughening of the ZrO₂ phase.     

PREPARATION OF NANOMETER ZrO2-8%Y2O3 POWDERS BY AZEOTROPIC DISTILLATION PROCESSING

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Mechanical wet-milling and subsequent consolidation of ultra-fine Al2O3-（ZrO2＋3%Y2O3） bioceramics by using high-frequency induction heat sintering

Alumina/zirconia composites were synthesized by wet-milling technique and rapid consolidation with high frequency induction heat sintering(HFIHS). The starting materials were a mixture of alumina micro-powder (80%, volume fraction) and 3YSZ nano-powders (20%). The mixtures were optimized for good sintering behaviors and mechanical properties. Nano-crystalline grains are obtained after 24 h milling. The nano-structured powder compacts are then processed to full density at different temperatures by HFIHS. Effects of temperature on the mechanical and microstructure properties were studied. Al2O3-3YSZ composites with higher mechanical properties and small grain size are successfully developed at relatively low temperatures through this technique.     

纳米ZrO2-Y2O3-La2O3热障涂层的结构与性能研究

采用喷雾造粒工艺在纳米ZrO2-8wt％Y2O3(8YSZ)基体中添加了纳米La2O3,并进行团聚、热处理,作为喷涂喂料.NiCrAlY(Ni-25Cr-5Al-0.5Y,wt％)作为粘结层材料,采用等离子喷涂技术制备热障涂层.对涂层的组织结构和性能进行了表征与分析.结果表明:喷涂后涂层相组成只有稳定的t相;涂层具有典型的等离子喷涂结构;添加纳米LaO3能够降低涂层的热导率,且涂层的结合强度随掺杂量的增多而提高.     

纳米ZrO2-8％Y2O3水相悬浮液分散稳定性研究

目的 探究Y2O3为8％的纳米ZrO2-8Y2O3(8YSZ)水相悬浮液的分散机理.方法 选用PAA、PEG600、PEG2000三种不同分散剂,在不同分散剂含量和pH值条件下,制备固相含量(以质量分数计)为20％的纳米8YSZ水相悬浮液.采用Zeta电位、粒度分布和悬浮液黏度对纳米8YSZ水相悬浮液的分散稳定性进行表征.结果 pH为中性时,悬浮液中分散剂PAA、PEG2000、PEG600的最佳用量(以质量分数计)分别为2.4％、2.4％、3.2％,对应的最低黏度分别为4.08、3.84、3.36 mPa·s.加入分散剂PAA后,纳米8YSZ等电点的pH值由6左移到4附近.当PH值为8时,纳米8YSZ颗粒的Zeta电位最高,达–44.5 mV.结论 纳米8YSZ水相悬浮液的分散稳定性与分散剂的种类、含量和pH值有关.仅添加分散剂或调节pH值均不能使纳米8YSZ水相悬浮液分散稳定.分散剂PAA同时具有静电稳定和空间位阻稳定的作用.分散剂的总体分散效果由高到低依次为PAA、PEG2000、PEG600.制备固相含量为20％的纳米8YSZ水相悬浮液的最佳条件为:pH=8,PAA含量为2.4％.此时悬浮液的分散效果最好,黏度最低,为2.56 mPa·s.