【作者】 朱义文；

【导师】 肖国庆； 严解荣；

【作者基本信息】 西安建筑科技大学 ， 材料工程， 2010， 硕士

【摘要】 文中介绍了通过添加稳定剂把单斜氧化锆转变为部分稳定的氧化锆的方法,考察了单一稳定剂对单斜氧化锆的稳定效果及规律,介绍了锆质制品中稳定化率含量对制品抗热震稳定性的影响。针对原材料类型、产地的不同对制品的性能产生不同的影响也做了简要的描述。随着钢铁冶炼技术的进步,钢材市场的需求,国内钢铁生产企业进行产品结构调整,一些深冲、超深冲等超低碳钢开发已成未来发展的必然趋势。这些高附加值的钢材生产,要求钢水在冶炼过程中尽量不使用含碳的耐火材料,传统的含碳耐火材料已不符合使用要求。另外,对于生产高钙钢来讲,在高温下,由于钙容易和钢包用含碳耐火材料(铝碳滑板)中的Al203反应,生成低熔点的铝酸钙,使得铝碳滑板的使用寿命大幅降低,很难满足正常生产的需要。由于Zr02材料具有和钢水不浸润、耐冲刷等性能,因此用锆质材料代替含碳耐材是理想的选择。由于锆质制品烧结温度较高,且热震稳定性极差,国内生产95%—Zr02滑板一般是采用CaO为稳定剂,制品的热震稳定性差,在使用过程中容易开裂,连用次数不超过2次。因此,开发抗热震稳定性不低4次的95%—Zr02滑板,可以节省钢材冶炼成本,降低工人劳动强度。氧化锆具有耐火度高、耐钢液侵蚀和冲刷等优良特性,但是纯氧化锆制品不容易制造。这主要是因为氧化锆从高温至室温所发生的相变,有约5—6%的体积膨胀,很难获得完整结构的烧制产品。在Zr02中添加某些金属氧化物,其阳离子半径与Zr4+半径相接近,能够在一定温度下单斜锆向四方晶、立方晶转化时,这些金属氧化物的阳离子固溶到到四方晶、立方晶结构中,温度降低时,能够抑制四方、立方晶向单斜结构转化,达到稳定晶格作用,称之为氧化锆稳定剂,如Y203、CaO、Al203、MgO、Ce02等。这些氧化物能与Zr02形成固溶体或复合体,通过晶体内部结构的改变,以及Zr02中晶格缺陷,从而抑制上述相变的发生,从而获得完好结构的氧化锆制品。目前,市场上销售的稳定氧化锆为Y203、CaO、稳定,原料质量不稳定,这对开发生产抗热震稳定性优良的锆质滑板来说有一定难度。因此,本试验从通过加入稳定剂,把单斜氧化锆稳定为部分四方、立方晶结构的稳定氧化锆,然后,用它为主要原料研制开发锆质滑板。试验中介绍了添加Y2O3、CaO、MgO的稳定氧化锆,研究了使用单一稳定剂时,在不同烧结温度下,其种类和含量变化对稳定相和稳定化率及稳定后原料的体积密度和显气孔率的影响。最后,确定滑板制品的稳定化率为35—55%,单斜锆为澳大利亚产化学锆,稳定剂为Y2O3、CaO。严格的生产制造工艺,研究出了抗热震稳定性不少于4次的锆质滑板。更多还原

【Abstract】 This paper introduces the methods by adding a stable monoclinic zirconia into a partially stabilized zirconia, this study investigated a single stabilizer on the stability of monoclinic zirconium oxide effects and rules, introduced quality products in the stabilization of zirconia content on the rate of product the impact of thermal shock resistance. For the raw material type, origin of the products of different properties have different effects have also done a brief description.As the iron and steel smelting technology, steel demand, domestic steel production enterprises to adjust product structure, Some depth flush, ultra flush and so on deeply the ultra low-carbon steel development already the inevitable trend which will become develops in the future. These high value-added steel products, molten steel in the refining process required minimal use of carbon refractories, traditional carbon refractories have not meet requirements. In addition, for the production of steel in terms of high calcium, high temperature, due to calcium and easy to use carbon ladle refractories (Al-C sliding) of Al2O3 reaction of calcium aluminate with low melting point, making the life of large aluminum carbon skateboard reduced, it is difficult to meet the needs of normal production. As the molten ZrO2 material with and without infiltration, erosion resistance and other properties, so instead of using zirconium carbon refractory material is ideal.As the zirconium high quality products, sintering temperature, and poor thermal shock resistance, the domestic production of 95%-ZrO2 skateboarding generally is used CaO as stabilizer, the products is poor thermal shock resistance, easy to crack during use, once a number of not more than twice. Therefore, the development of thermal shock resistance is not low four times 95%-ZrO2 skateboard, you can save the cost of steel smelting and reduce labor intensity. Zirconia has a high refractoriness, resistance to corrosion and erosion of liquid steel and other excellent features, but of pure zirconium oxide products is not easy to manufacture. This is mainly because zirconia to room temperature from high temperature phase transition occurred, about 5-6 percent of the volume expansion, is difficult to obtain a complete structure of the fired product. Add in some metal oxides ZrO2, the cation radius and Zr4+ radius are close, can under certain temperature monoclinic to tetragonal zirconia, cubic transformation, these metal oxide cation solution to the tetragonal, cubic crystal structure, the temperature is lowered, it can inhibit the square, cubic crystal structure to monoclinic transformation, to stabilize the lattice effect, known as zirconia stabilizer, such as Y2O3; CaO, Al2O3, MgO, CeO2, etc. These oxides form a solid solution with ZrO2 or complex, by changing the internal structure of crystals, and ZrO2, lattice defects, thus inhibiting the occurrence of the phase transition, which was intact structure of zirconia products. Currently, the market’s stabilized zirconia as Y2O3, CaO, stable, unstable quality of raw materials, which develop and produce excellent thermal shock resistance of zirconium quality skateboard is a certain degree of difficulty. Therefore, this study from by adding stabilizer, the stability of monoclinic zirconia as part of the square, cubic crystal structure of stabilized zirconia, and then use it as the main raw material research and development of zirconium skateboard.Experiments described add Y2O3, CaO, MgO of stabilized zirconia were studied using a single stabilizer, at different sintering temperature, the type and content on phase stability and stabilization rate and stable raw materials and bulk density were Porosity. Finally, to determine the stability of skateboard products was 35-55 percet monoclinic zirconia for the Australian production of zirconium chemicals, stabilizers Y2O3, CaO. Strict manufacturing process, developed a thermal shock resistance of zirconium of not less than fourth skateboard.更多还原